CAT Code Plug Pin-outs

[Peter Parts]

The narrow band 02 sensor used on oilheads does not give a constant proportional voltage in normal use, though an output ov about 0.5volts is equal to stochiometric burn. What happens is that the reading starts off either lean or rich, lets go with lean. The 02 sensor shows a lean burn, the ECU then adds fuel until the 02 shows rich, at which point the ECU removes fuel until the 02 shows lean, and so on. This gives an output that switches back and forth about 0.5volts, the rate this happens is called 'cross-counts' and this information is used to sense the correct operation of the 02.

The best way to diagnose an 02 failure is to 'scope the output to see the voltage swings in action. When an 02 fails, it tends to stay in one condition or get very lazy in its changes, and so is easy to spot.

 

BTW, apart from bosh at least one other manufacturer makes a plug-in 02 sensor for the oilhead.

 

Andy

 

That is very interesting to learn. I never knew the primitive 2.4 kept track of these cross-counts. So you'd have to spoof both the voltage as well as rig-up some kind of multivibrator NE555 to spoof cross-counts. (May take me a while to believe the Motronic 2.4 - or the Techlusion, recto verso - really does all that, no disrespect.)

 

But what about "CO pots" which are a kind of O2 sensor fooler used in Europe some? Would they pass the cross-counts criterion?

 

 

Footnote: OK, I can picture my fancy family bus lighting up a dashboard idiot lamp when the cross-count is low... but not the 2.4.

[T__]

Peter,, good questions..

 

What does "cross counts" mean?…..

 

Andy pretty well covered that.. On most (narrow band) closed loop fueling systems including the BMW 2.2 & 2.4 the fueling computer places more emphasis on when & why the 02 voltage crosses the center voltage (about .45 volts) than on what that voltage actually is.. The problem is the 02 sensor is so inaccurate when it gets out near the ends of voltage limits (below .2 & above .8 volts) that it really isn’t a usable range..

It’s difficult to find an analogy to compare with an 02’s operation but it is similar to riding & balancing a bicycle.. The idea is to balance the bicycle but also keep it on a given line & on the road.. That is done by moving the front wheel back & forth across it’s center many time per minute.. If you lock the handlebars in position on either side of center the bike won’t balance anymore.. You can turn them in one direction more than the other but you still have to go back across center to balance the bike.. It really doesn’t matter how far you turn the bars as long as you go back across center to keep your balance.. Now if you start turning the bars 20° to the right & only 5° to the left you will eventually be off the road..

 

 

 

About idle, I thought (at least for the 2.4 ECU) it is never in closed-loop at or near idle or near WOT. And it is also always on the matrix whenever you move the throttle…..

 

Most ALL computer controlled fueling systems are in closed loop at idle.. For sure the BMW Ma 2.2 & 2.4 systems… That is an important part of the emission test RPM operating range & converter protection range.. At higher loads the cat can react & burn off a rich mixture but at idle not so easy.. On unheated 02 systems there is always the possibility that the 02 will cool down & become unresponsive at

Idle but most modern vehicles have heated 02 sensors to allow full function at idle..

 

What is the way it handles the spoofing of the O2 sensor - does it subtract a constant voltage like .05 volts or divide the voltage to get a proportional decrement or what?…..

 

That is a good question & in all my testing I really never figured it out completely.. It isn’t voltage add or subtract as that won’t work.. On the narrow band 02’s they are very inaccurate once they get out of the stokeometric (sp) window so the fueling computer sees that as a no go zone so mainly uses cross counts to control fueling.. From what I could determine in running with a duty cycle meter on both the injectors & 02 sensor the Techlusion uses the 02 signal to guide it then substitutes a believable skewed cross count that tips the fueling input into the fueling computer to the rich side.. I tried running a duty cycle meter on both the actual 02 output & the spoofed 02 output & while similar in frequency they didn’t always act inversely connected.. It isn’t easy to spoof the 02 input into a fueling computer as the fueling computer needs to see not only fairly regular swings across the .45 volts center but also needs to see a fairly linear response to it’s fueling add or subtract.. If the voltage stays above or below .45 volts or doesn’t respond to the fueling computer add or subtract of fuel the fueling computer will just disregard it & go open loop..

One thing to keep in mind when trying to trick an 02 system is if it were as easy as adding a simple resistor or adding some extra voltage there would be many types of simple 02 spoofers on the market.. There are tons of IAT sensor spoofers & more than a few engine temperature sensor spoofers but no real functional 02 spoofers (that WORK) on the market,, there must be a reason..

 

When the O2 sensor is disconnected (with or without a Techlusion installed), does the ECU simply stay on the map all the time?….

 

It is always looking at the fueling map even when it is in closed loop,, that is needed so the fueling computer knows what cell to be in when it instantly needs to go open loop,, it also needs the mapping for spark control.. On most closed loop systems the fueling computer just disregards an errant or lazy 02 then uses RPM/Throttle position to follow mapping then trims that using the other sensors inputs to trim the main mapping.. On the 2.4 system the open loop mapping is pretty decent as far as emission output & converter protection as that is only loaded with cat equipped maps.. The 2.2 system has at least one & maybe more non cat equipped maps so those can go a bit richer with no 02 present & the correct CCP in place..

 

 

 

Twisty

 

 

[T__]

clip~

That is very interesting to learn. I never knew the primitive 2.4 kept track of these cross-counts. So you'd have to spoof both the voltage as well as rig-up some kind of multivibrator NE555 to spoof cross-counts. (May take me a while to believe the Motronic 2.4 - or the Techlusion, recto verso - really does all that, no disrespect.)

 

But what about "CO pots" which are a kind of O2 sensor fooler used in Europe some? Would they pass the cross-counts criterion?

 

 

 

 

Peter,

That is very interesting to learn. I never knew the primitive 2.4 kept track of these cross-counts. So you'd have to spoof both the voltage as well as rig-up some kind of multivibrator NE555 to spoof cross-counts. (May take me a while to believe the Motronic 2.4 - or the Techlusion, recto verso - really does all that, no disrespect.)…..

 

I doubt it keeps track of cross counts it’s just that it needs to see cross counts to control fueling.. If you are going to try to trick the system with something like a multivibrator NE555 you will also need to add additional injector pulse width.. The NE555 might be able to keep the system in closed loop but not in step with the 02 output..

That is the thing that had me wondering on the Techlusion.. I could never prove to myself that it actually used the original 02 output then spoofed that.. It always seemed more like it just sent a non related spoofed >.45/<.45 volt cross signal to the fueling computer then handled the fueling control against a fixed computer injector pulse width based on RPM/TPS.. Even if that were true it is still a good system as it keeps the 02 in the system so at idle it can instantly revert to full 02 control..

 

 

 

 

But what about "CO pots" which are a kind of O2 sensor fooler used in Europe some? Would they pass the cross-counts criterion?…

 

The CO pot ONLY works on the open loop maps .. With a closed loop system the fueling computer looks for 02 input & not a CO pot trim.. The CO pot is just an idle trim control,, as the throttle opens it becomes less & less effective (real similar to what an idle screw would do on a carbureted engine)..

 

Twisty

 

[David R]

Just to add information (hopefully to make up for some of what I took) Yesterday I figured I had the fuel set how I wanted it. Bike had 89 octane gas. I changed to olive green, 30 and 86 terimnals. All the bike did was ping. I was just leaving to go on a "spirited" ride with some others. First we stoopped and I topped up the tank with 93 octane. It took 5 gallons. Still pinging, so at the next stop I went back to the stock yellow CCP.

 

Matt told me at techlusion that if it pings I could cover it up with more fuel. So today I switched back to olive green and went with more fuel on all 3 pots and left the cruise pot all the way down. It pinged once on the way home and had a lot of power. Seat of the pants method only. When it has this much fuel, the bike runs like crap cold. It was just a test.

 

When I switched to the olive green CCP I pulled the plugs first. Kind of a dark grey. not black, not "coffee with cream brown" which I prefer.

 

Going to try pink today.

 

I have a 2 trace scope and the filters to check O2 sensors. Hooking it up is no big deal, but doing a dynamic test will take a passenger on the bike to catch and hold the trace. It will remember 40 screen shots in a row. So I can test before and after the techlusion.

 

This is good.... Going riding now though.

 

David

[Peter Parts]

All I learned about ECUs is from Adam Wade and Brad Black.

 

As far as I know, the ECU uses an A/D converter and reads voltage from the O2 sensor and reacts accordingly.

 

Some ECUs may be sophisticated enough to evaluate the condition (read: speed) of the sensor. They do this seeing how fast it reacts in the sense of reversals (AKA cross-counts). An O2 sensor can be slow enough (half a second, no kidding) to change negative feedback into positive and hence into disastrous oscillation. So it matters. But the ECU adjusts A/F by voltage, not cross-counts - as far as I can tell and I am still skeptical if the 2.4 (let alone the crude 2.2) does it at all.

 

I know Twisty1 means only the best in pedagogy when he introduces colorful if remote analogies like comparing the O2 sensor to "balancing" a bike. But...

 

 

[123abcXYZ789]

I think you are right about the pink one. That's the part number that the dealer shows as stock for my bike.

 

Too bad on the RT1200 surging! I guess everything requires tweaking.

 

Thanks!

[NonComp]

Too bad on the RT1200 surging! I guess everything requires tweaking.

I haven't worked on that bike, but I think that it is a lot harder to tweak than an oilhead. Apparently, it has two of everything, including O2 sensors.

[David R]

Update. With the first pot turned all the way down and the pink CCP in, the bike seems to run best.

It was the first pot that was causing the Herkity Jerkity throttle response and the Hi/Lo Idle thing. Power is great, but if its not smooth, its useless and annoying.

 

The other 3 pots are near factory recommended setting.

 

After I went to this setup, I rode 300 miles and pulled the plugs. White with small spots of "coffee with cream brown" on them. Just what I want. I get an occasional single ping. 93 octane. Timing is good. Bike starts great cold. Mileage for the last two tanks was 44 and 45 mpg. What more could I ask for?

 

David

[NonComp]

What more could I ask for?

That the bike stays like that for a while. Happy riding.

[Armando]

First pot being the Red one?

[David R]

First pot being the Red one?

 

First pot, green. Adds fuel all the time up to 4500 rpm.

 

Yes, I would like it to stay that way ....

 

David

[Marc01]

Hi, does anyone know what colour relays are for different countries?

Marc

[roger 04 rt]

Depending on model there were special Coding Plugs for Switzerland. What country and bike are you looking for?

[Marc01]

R1150RT 2002 Australia, mine has a yellow one, but have heard of some that have none. Just wondering.

Marc

 

[roger 04 rt]

After making many measurements with my Wideband O2 sensor setup ( here), my short answer is tha the Pink coding plug is standard and best for an R1150RT. The long answer is: R11XX Coding Plugs.

 

I don't know why some were shipped without plugs. There have been a lot of attempts on 1150s to get better performance by changing the coding plug. especially to reduce rough running at light engine loads. Some put in the Yellow plug and 1150GS intake tubes.

 

Does your motorcycle still have its oxygen sensor installed and connected?

 

The most reliable way to get much better running on an 1150RT is to shift the oxygen sensor lambda richer with an Innovate Motorsports LC-1 or something like it.

[Marc01]

Yes, it still has the oxygen sensor installed and connected.

Thanks

Marc