Possible starter button failure

[billfutt]

Hello all,

Just learned of this resource and thought I'd ask for some help. 2008RT 25k miles

The start button will not work once in a while but by repeated attempts and some "wiggling" it has always started... Until now. 

I hesitate to replace the entire switch assembly, not just because it's 300 bucks but I have no way of confirming with absolute certainty it is the switch. 

Anyone had this problem? If so, the fix?

Thank you

Bill in Kentucky

 

[dirtrider]

10 hours ago, Bill Crofutt said:

Hello all,

Just learned of this resource and thought I'd ask for some help. 2008RT 25k miles

The start button will not work once in a while but by repeated attempts and some "wiggling" it has always started... Until now. 

I hesitate to replace the entire switch assembly, not just because it's 300 bucks but I have no way of confirming with absolute certainty it is the switch. 

Anyone had this problem? If so, the fix?

Thank you

Bill in Kentucky

 

Morning Bill 

 

The easy way is to get a GS-911 (or dealer computer) on that motorcycle then see if the start switch, side stand switch, clutch switch are working correctly. 

 

On your 2008RT the start switch is a low amp switch that just tells the BMS-K (fueling computer) to operate the starter relay then run the starter. 

 

Your problem could very well be the start switch itself but your 2008 has the older switch assembly (prior to all foil switch issues on the later camhead BMW 1200 bikes.

 

Is your neutral light ON when the start problem is happening??  Or does the problem only happen with the transmission in gear & the clutch lever pulled in?

 

 You can manually verify all the start-inhibit interlocks using a volt-ohm meter but that is a lot of work (the GS-911 does it on one screen).

 

If you are pretty sure it IS the push button start switch itself then you can try partially disassembling the switch & spraying some switch contact cleaner in the switch contact area to see if that eliminates the problem. If so then that might be enough to eliminate your starting problem. If spraying contact cleaner into the switch helps eliminate the starting problem but the problem does come back then at least you know for sure that you have a start switch problem. 

 

If you want to dig into it farther then the wire colors you are dealing with at the connector on the end of the R/H switch pod wire pigtail is--   

(brown/blue  &  brown/orange)

 

The start push button simply connects the brown/blue to the brown/orange to tell the fueling computer to operate the starter (now this is on the switch side of the pigtail connector) 

 

But BMW doesn't make it easy as that brown/orange wire turns to green/yellow right where it enters the switch itself so best bet is to test at the brown/blue & brown/orange wires at the pigtail connector where it connects to the main wire harness.  

 

 

 

 

 

 

 

[billfutt]

Thank you for the info. I jumpered the wires and hear a relay click under the seat but that's all. I do not hear that when pressing the button but the sound would be drowned out by the starter motor WHEN the button does work.

A little back story, I bought it used and when picking up, it would not start but eventually did. The dealer replaced the clutch switch and battery. A few weeks after picking up, button did it again. That's when I learned that by wiggling (not pressing straight down on button) it would start every time... Until now. 

Nearest dealer is 2-1/2 hours away and I don't have access to any "reader" to help diagnose the issue. I think I'll try to disassemble the switch assembly and see if the switch contacts can be cleaned. I did spray a little contact cleaner but that didn't seem to help. Again, thank you and any further input would be most appreciated!

[dirtrider]

1 hour ago, billfutt said:

Thank you for the info. I jumpered the wires and hear a relay click under the seat but that's all. I do not hear that when pressing the button but the sound would be drowned out by the starter motor WHEN the button does work.

A little back story, I bought it used and when picking up, it would not start but eventually did. The dealer replaced the clutch switch and battery. A few weeks after picking up, button did it again. That's when I learned that by wiggling (not pressing straight down on button) it would start every time... Until now. 

Nearest dealer is 2-1/2 hours away and I don't have access to any "reader" to help diagnose the issue. I think I'll try to disassemble the switch assembly and see if the switch contacts can be cleaned. I did spray a little contact cleaner but that didn't seem to help. Again, thank you and any further input would be most appreciated!

Morning Bill

 

Reconnect  that cut  green/yellow then try jumping the brown/blue to the green/yellow.

 

I'm not sure where the spice is so by cutting the green/yellow that might have effected the other stop switch circuits. 

 

That click that you hear "might" be the starter relay, if so then your problem could be  in that area or between the starter relay & the starter or the starter itself.  (you need to define this before going too much farther into it) 

 

The starter relay is under the seat inside the plastic cover that also houses the diagnostic connector.

 

Starter Relay wire colors__  

red = 12v B+ into relay

Black = 12v out to starter solenoid with the relay energized

Brown/Violet = pull-in coil from BMS-K  (engine electronics computer)

Black/Yellow = pull-in coil B+ from BMS-K  (engine electronics computer)

 

Do not try to jump or short the Brown/Violet or the Black/Yellow as you can harm the very expensive BMS-K electronics computer.

 

You can unplug the relay connector then momentarily  short the (red) to the (black) as that should run the starter (just make darn sure you are going between the red & black & not one of the other 2 wires. 

 

   

[billfutt]

I did what your said, reconnected the green/yellow wire and jumpered to the brown/blue. 

Engine spun over just fine... I guess this would indicate a faulty starter button. 

I can't thank you enough for your help. I'll update this at I go along.

Edited May 9, 2023 by billfutt
Added "to"

[dirtrider]

33 minutes ago, billfutt said:

I did what your said, reconnected the green/yellow wire and jumpered to the brown/blue. 

Engine spun over just fine... I guess this would indicate a faulty starter button. 

I can't thank you enough for your help. I'll update this at I go along.

Afternoon Bill

 

I suppose you could always add a (stand alone) momentary push button between the green/yellow wire and  brown/blue. Then mount that button on a little bracket on the handlebars (possibly use the non-used R/H optional mirror mount hole)  

 

Leave the stock start button operational (just parallel it with the added switch circuit) then just use that added button in case the stock button doesn't work. 

[billfutt]

That's exactly what I did but wouldn't have known exactly how if it wasn't for your knowledge and help. I'll probably buy the right handlebar assembly but for now at least I'm up and running and know what the problem is.

Thank you (you saved the day) and a thanks to Dave D here for telling me about this group.

 

[Lowndes]

Billfutt -

 

Glad you got it going again.

 

This stuff is good for cleaning and protecting the contacts in handlebar switches.  It doesn't take much, just the shortest squirt you can do is more than enough, but the tiny little can I got four years ago is still going on 6 bikes.  Saves the hassle of disassembly, too.  The handlebar switches live a hard life out in the wind, dirt, and rain.

 

https://www.amazon.com/DN5S-2N-Deoxit-Contact-Cleaner-Deoxidizer/dp/B06XP32299/ref=sr_1_6?crid=ZCLGHLIJRP9&keywords=deoxit+d5+spray+contact+cleaner&qid=1683675314&sprefix=deoxit%2Caps%2C104&sr=8-6

 

[Indy Dave]

Welcome to the site, @billfutt! Glad you were able to sort this out and can ride to your hearts delight this summer! If you decide to replace the RH switch, keep an eye on ebay and also beemerboneyard.com.

 

A good parts resource for part numbers and cross reference is : https://www.realoem.com/bmw/enUS/select

 

Maxbmw parts also has a very similar interface, but they also have a photo and additional details of most of the parts: https://www.realoem.com/bmw/enUS/select

 

Bobsmotorcycles is also a great parts resource, with exceptional phone support, if you have to leave a message they call you back promptly. They have the largest inventory of vintage BMW parts in the country. Their website is undergoing a redesign currently.  https://www.bobsmotorcycles.com/--parts

 

If I had thought about it when we met, I could have hooked up my GS911 to your bike to diagnose your switch. 

[Mark Cross]

6 hours ago, Indy Dave said:

Welcome to the site, @billfutt! Glad you were able to sort this out and can ride to your hearts delight this summer! If you decide to replace the RH switch, keep an eye on ebay and also beemerboneyard.com.

 

A good parts resource for part numbers and cross reference is : https://www.realoem.com/bmw/enUS/select

 

Maxbmw parts also has a very similar interface, but they also have a photo and additional details of most of the parts: https://www.realoem.com/bmw/enUS/select

 

Bobsmotorcycles is also a great parts resource, with exceptional phone support, if you have to leave a message they call you back promptly. They have the largest inventory of vintage BMW parts in the country. Their website is undergoing a redesign currently.  https://www.bobsmotorcycles.com/--parts

 

If I had thought about it when we met, I could have hooked up my GS911 to your bike to diagnose your switch. 

 I have a good used switch. $50 plus 10 to mail. Mark 707-245-3289

[billfutt]

Thanks! Can you post a picture please to confirm it's the same and explain why did you replace it?

[Mark Cross]

I had stripped bike down for parts with worn  motor. 2009  police model. The heated grip switch has a light symbol.

 Mark

I have a picture in my phone text me 707-245-3289

[billfutt]

Well.... It's back. After installing a new switch things were fine for a short time but now the same problem is occurring. Just like before, sometimes it works and sometimes it doesn't. I can hear a relay clicking under the seat but that's it. I don't dare ride anywhere now since I don't know if it will start after shutting off. 

This problem was "fixed" by a dealer and I don't have a lot of confidence a different dealer will fix this issue. 

Anyone know if the clutch switch and the kickstand switch can be temporarily jumpered to see if  one of those is the problem?

Thank you all for any suggestions.

Bill

[Indy Dave]

Bill, sorry to hear your issue has returned. There is a procedure that checks the various safety switches. I think originally it was designed for the oil heads, but it worked on my hex head. I'm pretty sure I have a PDF of the procedure, but I'm not home right now. I'm sure that dirt rider has outlined it in previous threads, and if nothing else, I'm sure he'll be along shortly to either link to it or paste the procedure.

 

Good luck.

 

When I get home, if it hasn't been posted, I will link to it.

[dirtrider]

55 minutes ago, billfutt said:

Well.... It's back. After installing a new switch things were fine for a short time but now the same problem is occurring. Just like before, sometimes it works and sometimes it doesn't. I can hear a relay clicking under the seat but that's it. I don't dare ride anywhere now since I don't know if it will start after shutting off. 

This problem was "fixed" by a dealer and I don't have a lot of confidence a different dealer will fix this issue. 

Anyone know if the clutch switch and the kickstand switch can be temporarily jumpered to see if  one of those is the problem?

Thank you all for any suggestions.

Bill

Afternoon Bill

 

If you hear the starter relay click when you push the start button then the clutch switch and/or the neutral switch is working OK. 

 

Do you have a 12v test light or a voltmeter that will read 12v DC? If so we can talk you through some circuit testing.

 

With the starter relay clicking but no starter function that usually points to a starter relay (contact) problem, or an intermittent open in the wire between the starter relay & the starter solenoid, or an internal starter issue.    

[billfutt]

Thank you! I have both and the wiring diagram. Any help you can provide is greatly appreciated.

[dirtrider]

Morning Bill 

 

You will need to  remove the L/H side lower Tupperware to access the starter. (specifically the rear of the starter)

 

You are going to need to determine what part of the starter is (or isn't) getting 12v when you push the start button with the key turned on. 

 

You will only get a valid test WHEN the motorcycle won't start, if it is starting OK then your testing will show no problems. 

 

You will need either a 12v test light or a DC voltmeter.

 

See picture below for test points "A", "B", "C"

 

First place to test is "A", so hook a 12v test light (or voltmeter) to post "A" and to the battery (-) post. It should show battery voltage or bright test light all the time (does it?)

 

Now with the key-on push starter button. "A" should still show close to battery voltage or bright test light. (does it?)

 

Next, move your test light or voltmeter probe to "B" on the starter. That terminal should show no voltage or no test light lit. Next, turn key on then push the starter button, terminal "B" should NOW show close to battery voltage or bright test light. (does it?)

 

Next, move your test light or voltmeter probe to  "C" on the starter (leave wire from bike harness hooked to that terminal). That terminal should show no voltage or no test light. Next, turn the key on then push the starter button, terminal "C" should NOW show close to battery voltage or bright test light. (does it?)

 

If it passes all the above tests then you probably have a bad starter (you might try rapping side of starter with a hammer while holding starter button down with key on)--- (if it then cranks)  you are pretty sure you have internal starter issues -- DON'T do this before the above electrical tests or you will lose the ability to tell a bad starter from a bad starter solenoid.

 

If it doesn't pass one or more of the above tests tell us which ones & we can then tell you the next system to test in the starting chain.

 

[Indy Dave]

Just to follow up on my previous post, I misremembered  . . .  the procedure I referenced earlier is for troubleshooting cruise control and microswitches.   

 

[billfutt]

I tested voltage at A and B. Of course, the dozen plus times I hit the button it turned over except one time it hesitated a bit before turning over. No voltage at B momentarily. I'll check C a little later. But, getting it to NOT work is very frustrating. 

[dirtrider]

1 hour ago, billfutt said:

I tested voltage at A and B. Of course, the dozen plus times I hit the button it turned over except one time it hesitated a bit before turning over. No voltage at B momentarily. I'll check C a little later. But, getting it to NOT work is very frustrating. 

Afternoon Bill

 

Voltage at (B) only tells you something IF you also have voltage at (C).  

 

 

 

[billfutt]

I didn't follow your directions explicitly only because it's hard to get my probe on the terminal without nicking the insulation on the wire a little. However, after 50+ tries there was voltage at the C wire every time. It was disconnected from the solenoid. I'll try again later with it connected. 

[billfutt]

I placed the volt meter on C. Of course, it worked every time I hit the bottom until the battery was running low. On charger, will try again later.

[dirtrider]

4 hours ago, billfutt said:

I placed the volt meter on C. Of course, it worked every time I hit the bottom until the battery was running low. On charger, will try again later.

Afternoon Bill 

 

Maybe try running it until the engine is hot, the heat might make the problem more likely to show up. 

[billfutt]

Same... Can't get it to fail. I'm going to replace the relay and put the bike back together. If it fails again, I'll replace the starter.

Thank you for the help. I'm sure if I could have gotten it to fail the info you supplied would have provided an accurate diagnosis. 

I did notice with the relay in my hand, it sometimes hesitated very briefly to actuate. I'll update this post in case it could help someone else.

[billfutt]

On 6/12/2023 at 3:42 PM, dirtrider said:

Afternoon Bill 

 

Maybe try running it until the engine is hot, the heat might make the problem more likely to show up. 

Unless you have something else to try. I'll replace the relay but I'm open to suggestions of other possibilities. Connectors all look good, no corrosion.

[dirtrider]

2 hours ago, billfutt said:

Unless you have something else to try. I'll replace the relay but I'm open to suggestions of other possibilities. Connectors all look good, no corrosion.

Morning Bill 

 

Personally I would run a wire up from the starter "C" to a place near the dash or on the handlebars. (someplace you can see it)

 

Then install a small temporary 12v panel light (hook the "C" wire to one leg of the 12v light & ground the other leg. (leave enough wire length to reach the battery (+) post)

 

Then put the motorcycle back together & ride it as normal.

 

If by chance it doesn't crank over at some point then just look at that 12v panel light, if it lights then your starter problem is in starter.  If it doesn't light when you push the start button then your problem is most likely the starter relay itself, or the wire between the relay & the starter solenoid. 

 

If it just won't  crank over & the light won't light,  then just touch that wire to the battery (+) post as that by-passes everything except the starter & energizes the starter solenoid. (make DARN sure the transmission is in NUTRAL before touching that wire to the battery (+) post as that also by-passes all the starting safety interlocks.  

[billfutt]

The relay will be here at the local auto parts store tomorrow. I'll pick up a little light to do what you suggest.