GPS Power Mystery

[jdub53]

Background: I bought my 2013 R1200RT used in Nov. 2022, which came with the BMW Nav Prep kit which included a Nav IV mount. My Nav V GPS (which I kept when I traded my 2014 R1200GS for the RT) worked as expected in the Nav IV cradle, turning on only when I turned on the ignition key and giving me the "Power Disconnected" (or similar) message ~ 30 seconds after turning off the key. 

 

Although the Nav V never gave me one issue in nine years, I decided recently to "upgrade" and replaced it with a Zumo XT (which I now regret for many reasons, but that's a whole other issue). I sold the Nav IV cradle complete with power cord and connector which mated with the bike's two-pin aux plug connector with the red/white (+) and brown (-) wires in front of the steering head. For the XT's power, instead of splicing in a connector I used a Posi-Tap on each of the same two aux plug wires that the Nav IV cradle had connected to. 

 

The issue: About 50% of the time when I install the XT into its cradle (always with the bike off, and when it hasn't been ridden for a day or two) the XT immediately powers on although it is connected to a switched circuit which should be off/should have lost power 30 seconds after the bike was turned off the day before). Each time it does this, I confirm on the XT itself that its battery indicator is showing a charge and upon removal of the XT my multi-meter confirms 5.26 VDC at the XT cradle pins. The other 50% of the time when I insert the XT into its cradle under the same conditions (haven't ridden the bike for a day or so), the device acts as expected and does not power on, and I confirm then with my multi-meter there is no power at the pins. 

 

I'm stumped by A) how this supposed switched circuit on the bike is intermittently transmitting power with the bike off, and B) why this intermittent event only started when I tapped into the aux plug wires with the newer GPS. To the best of my knowledge, using a two-pin connector on the end of the XT's power cord should be no different than tapping directly into the exact same wires. 

 

Thoughts?

 

[dirtrider]

17 minutes ago, jdub53 said:

Background: I bought my 2013 R1200RT used in Nov. 2022, which came with the BMW Nav Prep kit which included a Nav IV mount. My Nav V GPS (which I kept when I traded my 2014 R1200GS for the RT) worked as expected in the Nav IV cradle, turning on only when I turned on the ignition key and giving me the "Power Disconnected" (or similar) message ~ 30 seconds after turning off the key. 

 

Although the Nav V never gave me one issue in nine years, I decided recently to "upgrade" and replaced it with a Zumo XT (which I now regret for many reasons, but that's a whole other issue). I sold the Nav IV cradle complete with power cord and connector which mated with the bike's two-pin aux plug connector with the red/white (+) and brown (-) wires in front of the steering head. For the XT's power, instead of splicing in a connector I used a Posi-Tap on each of the same two aux plug wires that the Nav IV cradle had connected to. 

 

17 minutes ago, jdub53 said:

 

The issue: About 50% of the time when I install the XT into its cradle (always with the bike off, and when it hasn't been ridden for a day or two) the XT immediately powers on although it is connected to a switched circuit which should be off/should have lost power 30 seconds after the bike was turned off the day before). Each time it does this, I confirm on the XT itself that its battery indicator is showing a charge and upon removal of the XT my multi-meter confirms 5.26 VDC at the XT cradle pins. The other 50% of the time when I insert the XT into its cradle under the same conditions (haven't ridden the bike for a day or so), the device acts as expected and does not power on, and I confirm then with my multi-meter there is no power at the pins. 

 

I'm stumped by A) how this supposed switched circuit on the bike is intermittently transmitting power with the bike off, and B) why this intermittent event only started when I tapped into the aux plug wires with the newer GPS. To the best of my knowledge, using a two-pin connector on the end of the XT's power cord should be no different than tapping directly into the exact same wires. 

 

Thoughts?

 

Morning jdub53

 

The system probably thinks that you have hooked up a battery charger so it brings the accessory circuit alive to accept it. I don't know what the circuit monitor voltage is but it could be as low a 5v or so.  

 

I have also seen-- You turn the key off after riding & the accessory circuit shuts down after a short time but the GPS is still in its delayed shutdown sequence. Then when the GPS finally shuts down it can, at times, trigger the ZFE controlled accessory circuit to came back alive. (something to watch for)

[jdub53]

4 hours ago, dirtrider said:

 

Morning jdub53

 

The system probably thinks that you have hooked up a battery charger so it brings the accessory circuit alive to accept it. I don't know what the circuit monitor voltage is but it could be as low a 5v or so.  

 

I have also seen-- You turn the key off after riding & the accessory circuit shuts down after a short time but the GPS is still in its delayed shutdown sequence. Then when the GPS finally shuts down it can, at times, trigger the ZFE controlled accessory circuit to came back alive. (something to watch for)

 

Thanks for the reply dirtrider, but again I can't understand why the scenario you mentioned regarding the bike's system sensing the XT's internal battery voltage and thinking it may be a battery charger wouldn't have also applied with the Nav V and its internal battery. Also, if this were the case I still can't understand why the XT doesn't turn on 100% of the time when I place it into the RT's cradle instead of only intermittently. I've never seen this situation with the Zumo XT mentioned by anyone on any of the forums I frequent, so curious if any other BMW riders/XT users have experienced it. 

 

I realize now I didn't mention in my first post that I always remove the GPS from its cradle upon returning home from a ride, usually before the bike's 30 second power cut-off is reached. Again, I did the same thing with the Nav V.  I also use the GPS on my Tenere 700, so it sits on a shelf in the garage until I know which bike I'm going to ride that day - hence the fact that the device gets installed prior to every ride instead of just sitting on the RT for days or weeks at a time.

[dirtrider]

54 minutes ago, jdub53 said:

 

Thanks for the reply dirtrider, but again I can't understand why the scenario you mentioned regarding the bike's system sensing the XT's internal battery voltage and thinking it may be a battery charger wouldn't have also applied with the Nav V and its internal battery. Also, if this were the case I still can't understand why the XT doesn't turn on 100% of the time when I place it into the RT's cradle instead of only intermittently. I've never seen this situation with the Zumo XT mentioned by anyone on any of the forums I frequent, so curious if any other BMW riders/XT users have experienced it. 

 

I realize now I didn't mention in my first post that I always remove the GPS from its cradle upon returning home from a ride, usually before the bike's 30 second power cut-off is reached. Again, I did the same thing with the Nav V.  I also use the GPS on my Tenere 700, so it sits on a shelf in the garage until I know which bike I'm going to ride that day - hence the fact that the device gets installed prior to every ride instead of just sitting on the RT for days or weeks at a time.

Afternoon  jdub53

 

Not necessarily, it could be they each have their own power-up sequence.

 

I don't power my GPS devices from the ZFE controlled accessory circuit as they can act strange at times depending on the GPS connected & timing. 

 

I just go with fused battery direct so I don't get a GPS shutdown when fueling up or during lunch breaks. 

[tpfeffer]

Check out this link on the BMWLT forum.  You're not alone with this issue.  I'm going to check out my XT mount to see if I have the same issue.  

https://www.bmwlt.com/threads/r1200rt-zumo-xt-mount.191960/post-1979938

 

Tom

[tpfeffer]

With the engine off and key in the lock position, I checked the two prongs on the Zumo XT mount and found zero voltage.  I bought the Zumo from Garmin December 2022.  Perhaps they had a problem with the circuit not powering down and made a product improvement to prevent battery drain when the ignition is off.  You might check with Garmin to see if this was a problem they fixed.  If so, perhaps they would provide the new and improved power cord.

 

The garmin is mounted on a 2013 R1200RT using the BMW accessory cable to get power from the existing power connector near the front shock. 

[RadioFlyer]

So here is a theory. 

 

The accessory port "listens" for a pulse signal from a compatible charger to know to keep the connection to the battery for charging. A ZFE compatible charger sends and repeats a pulse train to the accessory port. The pulse train starts with the charger presenting 12V to the port for 1 second. Then it waits for 150 milliseconds. Next it sends a series of ten 12V pulses each having a duration of 10 microseconds and spaced 100 milliseconds apart. It repeats this pulse train until it senses that the ZFE has connected it to the battery and then it starts its charging procedure.

 

The GPS power connector is activated/deactivated at the same time as the accessory port so there is a relationship there.

 

The XT cradle has what is known as a buck converter to efficiently step 12V down to 5V. Buck converters work by switching at a high frequency.

 

So the theory is that the high frequency signal (noise) from the XT cradle buck converter is being mistaken for the compatible battery charger handshake pulse train. This keeps both the accessory port and the GPS connector live and connected to the battery. The result is a gradual drain on the battery.

 

GPS units that work on 12V don't need a buck converter in the cradle. They don't experience the aforementioned issue.

 

 

[jdub53]

23 hours ago, tpfeffer said:

Check out this link on the BMWLT forum.  You're not alone with this issue.  I'm going to check out my XT mount to see if I have the same issue.  

https://www.bmwlt.com/threads/r1200rt-zumo-xt-mount.191960/post-1979938

 

Tom

 

Thanks for the link; describes exactly the perplexing and inconsistent issue I've been experiencing ever since installing a Zumo XT. 

 

The original XT power cord failed during one of my first rides with it. I intermittently got the "power disconnected" notification on the screen, confirmed by the device's internal battery icon showing it not charging. Turned off the device to conserve its battery as I knew I'd need the GPS for guidance a few hours later into the ride, but it kept turning itself back on and running off its battery, which started drawing down battery power. Called Garmin customer support when I got a chance, the rep figured the power cord's internal circuit breaker was bad and got a new one on its way to me. I removed the GPS from the cradle, stashed it in my tankbag and headed back home. Once home I popped the XT into the second cradle I'd just mounted on my Tenere 700 but hadn't yet a chance to use, went for a ride and everything worked fine. 

 

While I'd connected the first power cord on my RT to the bike's switched aux plug (same plug where my previous Nav V had been connected to), I decided to instead connect the new cord direct to the RT's battery. As I'd stated above, I always remove the GPS from my bikes when the bikes are sitting in the garage. Four days after my last ride on the RT with the new power cord working OK, the bike's battery was so low it wouldn't turn over the engine. I suspected this was not a coincidence, and that the XT's power cord was somehow killing the directly connected battery. I've read about some aftermarket USB sockets draining a bike's battery while sitting and nothing plugged in due to some parasitic draw, and it seems the XT's power cord may fall into the same category.  

 

Knowing that was totally unacceptable going forward, I changed the connection back to the RT's switched aux plug. While the XT continues to immediately turn on 50% of the time I install it into the cradle with the bike off, the bike's battery hasn't been drawn down since. Due to an unrelated debacle with Garmin sending me two different warranty replacement Zumo XTs, I now have a couple of new spare power cords and may try experimenting with them on this issue. I REALLY miss my nine-year-old, trouble-free Nav V!

 

BTW, the XT's power cord on my T7 is also connected to a switched aux plug and none of these issues exist on that bike. Totally different electrical system from the RT, I know. 

 

Edit:  Hmm, my last paragraph about the T7 got me thinking. If I connected the RT's XT power cord to a switched circuit that depowered immediately with the ignition key being switched off, all of this should be moot. The bikes battery couldn't be drawn down by any parasitic draw because no power would be available. 

 

Anyone know of a switched circuit (horn? headlight?) the CANbus would allow the low current draw GPS to run off of with no faults thrown?

 

 

[rockitcity]

Hello all, new user to this site, although I have been browsing (lurking) for a while.  Thought I'd join in the fun since I am the original poster of the thread mentioned in bmwlt.com (same user name).

 

So, no real new insight as to why the Zumo XT keeps the battery circuit live, but I have determined a solution to keep it from draining the battery.  I simply leave the Zumo in the cradle for 15-30 seconds while I am taking off my gear until it exhibits the "external power lost" message.  Then I remove the Zumo and power stays off to the cradle.  Of course, this requires me to use the Zumo every time I ride, which isn't always necessary, but I do find it useful just to view the map and upcoming turns.  I am thinking of getting one of these security screws and just leaving it on the bike,  Would be good for pit stops anyway.  https://www.motopumps.com/shop/zumo-xt-security-lock

 

Yeah, it would be nice if it didn't drain the battery!

 

[DBULL]

On my 2019 RT1250, I installed an XT with its mount fixed onto the BMW mount.  It fits into that space like it was made for it.  I spliced into the cable that was to the BMW GPS power, and there has been no issue with turning on/off for me.  The BMW does power down in a minute or two which then sends the XT into its powering down.  I found that it acts the same as I had it on my 2010RT.  Just my .02.  

[rockitcity]

Thanks for the reply Dbull.  Well I changed the oil on my camhead last week, and reset the service reminder (love that Motoscan app.)  In the course of doing so, I did not have my Zumo XT mounted in its cradle.  Sure enough, I started to go out for  ride today and click, nothing.  Battery dead.  This was after 5 days sitting. Yeah, not enough riding, but I don't commute daily anymore.  I had forgotten to mount the Zumo and let it go through its power off sequence so the cradle stayed live and drained the battery.

 

As I mentioned above, if I wait to remove the Zumo until it displays its "power lost" message, there is no drain on the battery and the bike can sit for weeks without issue.  But if I turn on the ignition for whatever reason and power off without the Zumo mounted It will suck the battery dry.

 

Does your 2019 RT require you to use the Garmin power adapter with your Zumo? (I expect it would.) If so, it would be interesting to see if your cradle measures 5V at the pins without the Zumo mounted with an ignition on-off cycle. Or, does BMW provide 5V power directly to the Zumo through it's wiring? (I suspect not)

 

Anyway, it seems the best solution may be to use the security screw and leave the Zumo on the bike all the time.  That way, it will always power cycle off and keep the battery fresh.

[wbw6cos]

Is it possible to wire in an on/off switch?

[DBULL]

I don't use a power adapter, since I simply added the Garmin mount right onto the bike's mount with four longer screws and four spacers, so i replaced the Nav with the XT, and it seems to be working fine. (turns off 'external power lost') after about 1 or 2 minutes.  I rarely take it out of the mount except at hotel on trip (in the garage it stays in).    I did not use the adapter.  I'll see if I can get a reading today when I clean the bike after my trip home from GA and let you know.  For my power, I use the BMW cable that went to the GPS and spliced in.  Simple short proceedure.  You do not need to take the entire bike apart.  I think it took all of 45 minutes.  

 

[jdub53]

After doing some more research this morning with the XT on my RT, it appears what @rockitcity posted above is the key: Leaving the XT in its cradle at least until the "Power Disconnected" message appears a minute or so after the bike's ignition is turned off is the only way the XT's cradle/power cord will fully turn itself off from drawing any power from the bike's battery when connected to the RT's aux power lead. 

 

My findings, with the bike not having been ridden for a few days and using my digital multimeter:

1. Verified 0.0 VDC measured at the two pins in the XT cradle. Installed the XT into the cradle, and as expected it did not power on by itself.

2. Turned on the bike's ignition, the XT powered up and I turned off the key after ~ 10 seconds.

3. Removed the XT after a few seconds / well before the "Power Disconnected" message, immediately measured 5.26 VDC at the cradle. Checked again after several minutes, still 5.26 VDC.

4. Placed the XT in the cradle and as expected it immediately powered up on its own. Turned on the bike's ignition for ten seconds, then switched it off.

5. In ~ one minute, XT displayed the "Power Disconnected" message. Immediately removed it from the cradle (before it had actually turned itself off), and measured some residual voltage dwindling to 0.0 VDC withing seconds. Checked again several minutes later, still 0.0 VDC.

6. Placed XT into the cradle again, and it did not power on by itself. Turned on ignition key, XT powered up, and within seconds I manually turned it off by pressing its power button for a second. Removed it from the cradle, and verified 5.26 VDC at the pins. Checked again several minutes later and still 5.26 VDC at the cradle.

7. Placed XT into the cradle again, it powered up by itself as expected. Turned on ignition key for ten seconds, then switched off and within seconds pressed XT's power button for five seconds until it asked if I wanted to turn it off. Pressed Yes button, unit turned off, removed it from cradle right away and verified 5.26 VDC at the pins. Checked again several minutes later and still 5.26 VDC at the cradle.

 

To me these checks verified:

1. The only way that the Zumo XT's power cord will totally disconnect from its power source/draw zero power is for the XT device to verify on the screen "Power Disconnected".

a) On BMWs, when the XT power cord is connected to an aux power source with a delayed power disconnect as determined by the bike's ZFE computer, removing the XT device before power is disconnected by the ZFE will result in a continuous power draw by the XT's power cord (what once killed my RT's battery in four days). Apparently the ZFE interprets removal of the XT before the ZFE disconnects power as some kind of required draw or access requirement to the bike's battery.

b) On my T7, because the XT power cord is connected to switched power which is 100% controlled by the ignition switch (no delay), the "Power Disconnected" message appears as soon as I turn off the ignition key. Anytime the key is off, there is 0.0 VDC at the XT cradle.

2. As long as I keep the XT power cord on my RT connected to the ZFE-controlled aux power wires, I have no choice but to wait at least a minute (for the ZFE to cut power) before removing the XT from the cradle unless I'm OK with the continual power draw which will kill the bike's battery within a week if the bike sits unridden or isn't plugged into a charger.

3. The only way I can remove the XT from the RT's cradle without waiting for a minute and to have no power draw is to rewire it to a power source which is immediately turned off with the ignition key (just like on my T7). This is what will work best for me, and I'm still going to try rewiring the XT's power cord to the RT's horn wires or parking light wires. In 20 years of using GPS devices on motorcycles, I've never had to worry before about the GPS power cord killing my bike's battery but I guess this is "progress"?!?!

4. Because power to the XT's power cord is never cut when wired straight to the bike's battery (the XT can never display the "Power Disconnected" message when wired this way, because power is never lost), based upon my findings that means 5 VDC should be always be present at the XT's cradle whether or not the XT is installed. Unless I'm missing something, this means that any XT wired this way should kill the bike's battery in short order due to the continual power draw if not ridden often or kept on a charger. If true, I'm surprised this hasn't been more of an issue unless an XT turned off and always kept in the cradle kills the power draw to 0.0 VDC all by itself. 

 

I've checked the Garmin website and their on-line Zumo XT manual about power draw, and all I can find is:  Current Draw of the zumo XT Motorcycle Power Cable When the zumo XT is NOT connected to the motorcycle charging mount, the parasitic current draw of the Motorcycle Power Cable is 150uA @ 12V.

Current Draw of the zūmo XT Motorcycle Power Cable | Garmin Customer Support

[DBULL]

SOLVED!!

[jdub53]

4 hours ago, wbw6cos said:

Is it possible to wire in an on/off switch?

 

Installing such a switch at the XT power cord connection point is doable and would certainly take care of this issue, as long as I remember to switch it off after every ride.

 

Being a KISS principle guy, the simplest way I can think of to address the XT's power cord complication is to find a suitable switched power wire on my RT that's instantly controlled by the ignition switch both on and off. Hoping soon to try different connection points until I find one that works without throwing CANbus faults and will report back here.

[wbw6cos]

Thanks.  Lowndes showed me a simple USB port that is switchable.  I am thinking about configuring one for my Spot Trace in the right side compartment.

[rockitcity]

7 hours ago, wbw6cos said:

Is it possible to wire in an on/off switch?

If I have to do that I might as well go back to using the DIN power connector and plug it in each time.

[rockitcity]

3 hours ago, jdub53 said:

After doing some more research this morning with the XT on my RT, it appears what @rockitcity posted above is the key: Leaving the XT in its cradle at least until the "Power Disconnected" message appears a minute or so after the bike's ignition is turned off is the only way the XT's cradle/power cord will fully turn itself off from drawing any power from the bike's battery when connected to the RT's aux power lead. 

 

My findings, with the bike not having been ridden for a few days and using my digital multimeter:

1. Verified 0.0 VDC measured at the two pins in the XT cradle. Installed the XT into the cradle, and as expected it did not power on by itself.

2. Turned on the bike's ignition, the XT powered up and I turned off the key after ~ 10 seconds.

3. Removed the XT after a few seconds / well before the "Power Disconnected" message, immediately measured 5.26 VDC at the cradle. Checked again after several minutes, still 5.26 VDC.

4. Placed the XT in the cradle and as expected it immediately powered up on its own. Turned on the bike's ignition for ten seconds, then switched it off.

5. In ~ one minute, XT displayed the "Power Disconnected" message. Immediately removed it from the cradle (before it had actually turned itself off), and measured some residual voltage dwindling to 0.0 VDC withing seconds. Checked again several minutes later, still 0.0 VDC.

6. Placed XT into the cradle again, and it did not power on by itself. Turned on ignition key, XT powered up, and within seconds I manually turned it off by pressing its power button for a second. Removed it from the cradle, and verified 5.26 VDC at the pins. Checked again several minutes later and still 5.26 VDC at the cradle.

7. Placed XT into the cradle again, it powered up by itself as expected. Turned on ignition key for ten seconds, then switched off and within seconds pressed XT's power button for five seconds until it asked if I wanted to turn it off. Pressed Yes button, unit turned off, removed it from cradle right away and verified 5.26 VDC at the pins. Checked again several minutes later and still 5.26 VDC at the cradle.

 

To me these checks verified:

1. The only way that the Zumo XT's power cord will totally disconnect from its power source/draw zero power is for the XT device to verify on the screen "Power Disconnected".

a) On BMWs, when the XT power cord is connected to an aux power source with a delayed power disconnect as determined by the bike's ZFE computer, removing the XT device before power is disconnected by the ZFE will result in a continuous power draw by the XT's power cord (what once killed my RT's battery in four days). Apparently the ZFE interprets removal of the XT before the ZFE disconnects power as some kind of required draw or access requirement to the bike's battery.

b) On my T7, because the XT power cord is connected to switched power which is 100% controlled by the ignition switch (no delay), the "Power Disconnected" message appears as soon as I turn off the ignition key. Anytime the key is off, there is 0.0 VDC at the XT cradle.

2. As long as I keep the XT power cord on my RT connected to the ZFE-controlled aux power wires, I have no choice but to wait at least a minute (for the ZFE to cut power) before removing the XT from the cradle unless I'm OK with the continual power draw which will kill the bike's battery within a week if the bike sits unridden or isn't plugged into a charger.

3. The only way I can remove the XT from the RT's cradle without waiting for a minute and to have no power draw is to rewire it to a power source which is immediately turned off with the ignition key (just like on my T7). This is what will work best for me, and I'm still going to try rewiring the XT's power cord to the RT's horn wires or parking light wires. In 20 years of using GPS devices on motorcycles, I've never had to worry before about the GPS power cord killing my bike's battery but I guess this is "progress"?!?!

4. Because power to the XT's power cord is never cut when wired straight to the bike's battery (the XT can never display the "Power Disconnected" message when wired this way, because power is never lost), based upon my findings that means 5 VDC should be always be present at the XT's cradle whether or not the XT is installed. Unless I'm missing something, this means that any XT wired this way should kill the bike's battery in short order due to the continual power draw if not ridden often or kept on a charger. If true, I'm surprised this hasn't been more of an issue unless an XT turned off and always kept in the cradle kills the power draw to 0.0 VDC all by itself. 

 

I've checked the Garmin website and their on-line Zumo XT manual about power draw, and all I can find is:  Current Draw of the zumo XT Motorcycle Power Cable When the zumo XT is NOT connected to the motorcycle charging mount, the parasitic current draw of the Motorcycle Power Cable is 150uA @ 12V.

Current Draw of the zūmo XT Motorcycle Power Cable | Garmin Customer Support

Thanks for the detailed analysis jdub.  Let us know if you find a suitable point to splice into, although I usually hate messing with factory wiring. Except maybe those crappy headlight connectors, but that is another story...

[rockitcity]

4 hours ago, DBULL said:

I don't use a power adapter, since I simply added the Garmin mount right onto the bike's mount with four longer screws and four spacers, so i replaced the Nav with the XT, and it seems to be working fine. (turns off 'external power lost') after about 1 or 2 minutes.  I rarely take it out of the mount except at hotel on trip (in the garage it stays in).    I did not use the adapter.  I'll see if I can get a reading today when I clean the bike after my trip home from GA and let you know.  For my power, I use the BMW cable that went to the GPS and spliced in.  Simple short proceedure.  You do not need to take the entire bike apart.  I think it took all of 45 minutes.  

 

Thanks Dbull.  So I guess BMW has something internal to the newer bikes that steps down the 12V to 5V for the Nav since they do use Garmin systems. It would be interesting to see if your cradle powers off or not as jdub described in his post. Thanks for all the help.

[lkraus]

1 hour ago, rockitcity said:

Thanks Dbull.  So I guess BMW has something internal to the newer bikes that steps down the 12V to 5V for the Nav since they do use Garmin systems. It would be interesting to see if your cradle powers off or not as jdub described in his post. Thanks for all the help.

The mounts for Navigator IV, V, and VI, like the Zumo 6xx and 5xx series, provide 12V at the contact pins and the GPS makes the conversion to lower voltage internally. 

When the power is disconnected from the mount,  the XT (like the Navigators and Zumos) only goes to sleep, which allows for faster startup after a short stop.  It is still using power from the internal battery.  You must press and hold the power button and then agree to the confirmation message to shut it down completely.

 

When I received my XT, I connected the motorcycle mount to a 13.6V regulated power supply with an ammeter inline.

The supplied mounting cord and converter produced 5.24 V at the pins with the 13.6 V input. 

With the XT powered up, Brightness level, Current draw (mA) at 13.6V was:
20%, 420
50%, 430
70%, 450
80%, 480
90%, 520
100%, 580

Changing between day or night mode made no difference in current draw, only a changed brightness level caused a current change. The internal battery was very low and charging,  so current draw with a full battery might be less.

The motorcycle mount, the XT and converter together draw 2.44 mA in sleep mode (after single press of the power switch).

They draw 0.87 mA powered off (after power button held down and shut down confirmed on screen).

With the XT removed from the mount, the converter draws 0.15 mA. Not much, but not zero.

 

With the XT mounted and wired to the BMW GPS connector, I've found that the time after ignition off until the ZFE shuts down the circuit varies quite a bit.  Occasionally, it is only 20-30 seconds.  More often it takes 10-15 minutes and I've seen it take up 30 minutes before I got tired of watching and powered down the GPS manually.  I usually don't care how long it takes, unless I'm listening to music at a gas stop and it goes to sleep while I'm not looking.  I power off the XT completely at the end of the day (while still in the mount) and I seldom leave the XT in the mount overnight. 

[jdub53]

4 hours ago, jdub53 said:

To me these checks verified:

 

4. Because power to the XT's power cord is never cut when wired straight to the bike's battery (the XT can never display the "Power Disconnected" message when wired this way, because power is never lost), based upon my findings that means 5 VDC should be always be present at the XT's cradle whether or not the XT is installed. Unless I'm missing something, this means that any XT wired this way should kill the bike's battery in short order due to the continual power draw if not ridden often or kept on a charger. If true, I'm surprised this hasn't been more of an issue unless an XT turned off and always kept in the cradle kills the power draw to 0.0 VDC all by itself. 

 

 

I kept thinking about item #4 from my post earlier today (quoted above) regarding Zumo XT power cords connected direct to a bike's battery, and then I realized I had a very easy way to test that without disturbing my current set-up so I did. I was right.

 

Because of Garmin's circus of errors in trying to provide me with a warranty replacement for my XT bought in March 2023, I have several spare power cords and cradle mounts. I connected one of the spare power cords to a spare cradle mount, then connected the power cord wires direct to my battery.

 

After confirming the same 5.26 VDC at the pins that I see via the ZFE/aux plug connection, I installed the XT into the mount and as expected it immediately turned on. After leaving it installed for about 30 seconds, I popped the XT off the cradle and as expected the XT immediately displayed the "Power Disconnected" message and then soon shut itself off.

 

I checked the mount's pins, and as expected 5.26 VDC was still present as it was still connected directly to the battery. Five minutes later I checked again, and as expected still 5.26 VDC at the pins.

 

This verifies that once an XT is removed from a cradle/power cord connected direct to a bike's battery, the same 5.26 VDC remains a constant which is what killed my RT's battery via the ZFE/aux plug connection a few weeks ago.

 

No way am I hooking up my XT direct to my bike's battery because 1) I don't keep the XT in the cradle all the time (impossible to do so with two bikes) and 2) I've never kept my bikes on chargers all the time and I'm not going to start now. Back to looking at an alternate switched power source on the RT.

[RadioFlyer]

4 hours ago, jdub53 said:

 

I kept thinking about item #4 from my post earlier today (quoted above) regarding Zumo XT power cords connected direct to a bike's battery, and then I realized I had a very easy way to test that without disturbing my current set-up so I did. I was right.

 

Because of Garmin's circus of errors in trying to provide me with a warranty replacement for my XT bought in March 2023, I have several spare power cords and cradle mounts. I connected one of the spare power cords to a spare cradle mount, then connected the power cord wires direct to my battery.

 

After confirming the same 5.26 VDC at the pins that I see via the ZFE/aux plug connection, I installed the XT into the mount and as expected it immediately turned on. After leaving it installed for about 30 seconds, I popped the XT off the cradle and as expected the XT immediately displayed the "Power Disconnected" message and then soon shut itself off.

 

I checked the mount's pins, and as expected 5.26 VDC was still present as it was still connected directly to the battery. Five minutes later I checked again, and as expected still 5.26 VDC at the pins.

 

This verifies that once an XT is removed from a cradle/power cord connected direct to a bike's battery, the same 5.26 VDC remains a constant which is what killed my RT's battery via the ZFE/aux plug connection a few weeks ago.

 

No way am I hooking up my XT direct to my bike's battery because 1) I don't keep the XT in the cradle all the time (impossible to do so with two bikes) and 2) I've never kept my bikes on chargers all the time and I'm not going to start now. Back to looking at an alternate switched power source on the RT.

 

Great investigative reports. Thanks for posting.

 

[lather]

Is this a flaw in the XT? Lf so, anyone know if it has been fixed on the XT2?

[RadioFlyer]

1 hour ago, lather said:

Is this a flaw in the XT? Lf so, anyone know if it has been fixed on the XT2?

It is more a function of the cradle than it is the XT. 

[lather]

Right, a flaw in the cradle design. I appreciate the correction. 

[DBULL]

This morning, I washed and cleaned the bike after 7 days of riding in rain, dirt, wash out on the GA back roads.  Took GPS off to wash.  With the bike off, I put the GPS back in its cradle and it did not turn on (as it was designed to not turn on).  Not trying to drag this convo on longer, but reminder I used the BMW power TO the cradle in the bike, splicing into it with the XT.    I'm not great with electronics, but very happy with this result.   

 

 

[lkraus]

I don't see a fault in the design of the mount or voltage converter. It's the ZFE that is keeping the circuit (and possibly itself) active and causing a problem for some users. The empty mount alone only draws 0.15 mA, which is negligible and similar to other converters and USB adapters. I see figures of 30-50 mA given for maximum reasonable parasitic loss, and typical RT loss as 0.60ma, so 0.75mA should not be a problem.  Simply having 5.6V at the pins does not represent a power loss, it's just potential until the circuit is completed. The voltage converter is only using 0.00192 W, so little that Garmin can design for a direct-to-battery hookup.

 

As Dirtrider suggested earlier, the ZFE may be seeing the load as a BMW battery charger. Maybe keeping itself active to keep the circuit working is drawing additional power? Not a problem with incoming power from a charger to make up for any power use by the ZFE, but in this case it could be draining the battery.  I do not understand why this would happen with some bikes but not others. 

 

My RT, with the XT connected to the BMW GPS connector, always shuts down the GPS circuit after ignition-off, though the time delay does vary quite a bit. There is then no voltage at the mount pins until the ignition is turned on.  

 

@jdub53, the "Power Disconnected" message is only a warning that the XT to going into power saving mode, or sleep, which blanks the screen, but still maintains your location and route progress. See Page 1 of the manual. The XT is not completely shut down until you press and hold the power button down and then agree to "Turn off the device?"  Sleep mode drastically reduces power use, but on the mount it still uses almost three times the power of a complete shutdown.  Off the bike, sleep mode uses the internal battery, which can be difficult to recharge if it becomes totally depleted between rides.  You do not need to wait for the XT to recognize that power has been lost to shut it down, just hold the button down at any time.

 

 

[lather]

Interesting info about the low current draw, I would have expected more. For what is is worth I have a Zumo 390 and 396 and don't plan to upgrade since I have 5 bikes all with Garmin power supplies for the 390 and 396 which appear to be incompatible with the XT.

On my RT which does not  have  a BMW GPS mount my garmin harness is connected to a Touratech Fuse block which I assume the original owner installed to power his auxiliary lights. I simply added circuits for my Zumo and radar detector. All circuits are hot only with ignition on. 

[jdub53]

17 hours ago, lkraus said:

@jdub53, the "Power Disconnected" message is only a warning that the XT to going into power saving mode, or sleep, which blanks the screen, but still maintains your location and route progress. See Page 1 of the manual. The XT is not completely shut down until you press and hold the power button down and then agree to "Turn off the device?"  Sleep mode drastically reduces power use, but on the mount it still uses almost three times the power of a complete shutdown.  Off the bike, sleep mode uses the internal battery, which can be difficult to recharge if it becomes totally depleted between rides.  You do not need to wait for the XT to recognize that power has been lost to shut it down, just hold the button down at any time.

 

 

 

I've read the manual. In all of my usage above, I was generically using the phrase "turned off" to mean the XT's screen had gone blank either by itself following the Power Disconnected message, or by me pressing the device's on/off switch momentarily or for the five seconds required to get the Turn Off inquiry. I'd noted in one of my posts that I'd used both switch press methods as part of my research of this issue.

[jdub53]

13 hours ago, lather said:

On my RT which does not  have  a BMW GPS mount my garmin harness is connected to a Touratech Fuse block which I assume the original owner installed to power his auxiliary lights. I simply added circuits for my Zumo and radar detector. All circuits are hot only with ignition on. 

 

Any chance you know where the Touratech fuse block is wired to for its switched power source? Or, since you mentioned aux lights, maybe it's connected to a separate light switch which triggers a relay connected to...???

[lather]

I do not know how it is wired. I will look today and see if I can figure it out.

 I can't see how the Touratech module is connected to the BMW wiring. It is not connected to the battery. I am pretty sure the battery leads and trigger lead are routed along with the leads for the auxiliary light and they are zip tied to the OEM battery harness. I recently changed my sparkplugs and dont feel like pulling the plastic off again to investigate since the crash bars make that job a PIA. However I found some info online that shows tyhe suggested connection, it says the triger wire is usually spiced into the tail light wire. See linked photo:

https://www.carousell.sg/p/bmw-touratech-tps-15-can-bus-fuse-block-relay-switch-gs-rt-1200-1072354803/ 

 

and  apic of my installation

Edited May 4, 2023 by lather
update

[jdub53]

Mission accomplished. 

 

After much consultation with the wiring diagrams in my Haynes manual and testing a few other potential power sources, my Zumo XT power cord is now drawing its switched power from one of the two grey/blue wires at the headlight connection plug. Those wires each provide power to the side/parking lights within the headlight assembly, with their power controlled directly by the ignition switch position. All lights still work as before, and with the XT in its cradle it powers on when the ignition switch is turned on and within seconds of the ignition switch being turned off the Power Disconnected notification is displayed. Perfect, just like the XT works with the switched power source on my T7.

 

No more worrying about the XT power cord draining the RT's battery as it did a few weeks ago, no more waiting for the ZFE to cut power to the aux power plug before I can remove the XT from its cradle without worry about the power drain, and if I want the XT to remain on while getting gas, etc., I'll just press Cancel when the Power Disconnected notification is displayed so the XT will remain on via its internal battery. 

 

[rockitcity]

Thanks for that info.  Did you have to take things apart to get to the wiring, and did you use a hard splice (ie: cutting factory wiring) or come up with a suitable adapter for the existing wiring?

[jdub53]

1 minute ago, rockitcity said:

Thanks for that info.  Did you have to take things apart to get to the wiring, and did you use a hard splice (ie: cutting factory wiring) or come up with a suitable adapter for the existing wiring?

 

No disassembly required to access the wires on the headlight connector; just reach underneath the instrument panel and unplug it from the headlight assembly while standing on the right side of the bike. You should then have sufficient working room.

 

I used PosiTaps to connect the wires. Discovered these years ago along with the other products from this company, and that's all I use now for splicing, etc.

 

https://www.posi-products.com/posiplug.html