question

[JamesW]

Well, here's a stupid idea. Why can't you take your '04RT to an automotive store that has a generic computer diagnostic tool that can read fault code data from car computers and have it connected up to your beemer bike and wahlah, out comes any registered fault codes? I think data having to do with emission related issues is supposed to be standard access throughout the automotive industry, I think? So why wouldn't the Bosch Motronic 2.4 computer in our bikes work the same? Also, I wonder where the idea that pulling fuse F5 resets the computer came from? And let's say that an action such as pulling the code plug results in a fault code being registered and then the code plug is re-installed which is corrective action which would not clear a registered fault code but so what. What does it hurt to have a stored fault code if the condition that produced it is corrected? In other words go remove and replace your code plug all you want, what does it hurt?

[Joe Frickin' Friday]

Well, here's a stupid idea. Why can't you take your '04RT to an automotive store that has a generic computer diagnostic tool that can read fault code data from car computers and have it connected up to your beemer bike and wahlah, out comes any registered fault codes? I think data having to do with emission related issues is supposed to be standard access throughout the automotive industry, I think? So why wouldn't the Bosch Motronic 2.4 computer in our bikes work the same?

 

For years now car ECU's have been required to be OBD-II compliant. I don't believe bikes are held to the same standard.

 

Also, I wonder where the idea that pulling fuse F5 resets the computer came from?

 

That is indeed the fuse for the Motronic. On the 1100 bikes ('96-'01), the fault codes were readable by the user without the need for an interface computer. Pulling the fuse would eliminate any fault codes that had been stored.

 

I don't know whether the same fault-code-clearing behavior exists on the 1150 bikes like your '04 (can someone else confirm?), but I do know that pulling fuse 5 on these bikes causes the Motronic to "forget" the TPS voltages corresponding to idle and WOT.

[JamesW]

You know right about now I would even be happy if I could even find the diagnostic connector. I thought it was under the seat and a 2 pin or maybe 3 pin plug but I have looked everywhere under seat and the 2 quick to remove little side panels and no connector. Bike is 04RT. Looks like there is 12 volts from F5 on one pin and maybe data on the other? I would probably be well advised to just except the beast for what it is and just ride it but you know the story about curiosity and the cat.

[Haynes]

I think the diagonstic plug for the 04 RT is the round plug clipped into a bracket in the tail section.

[JamesW]

Thanks Keith, you is right, that's where connector is. Stupid old me, I looked right at it and didn't recognize it.

[Mulepick]

Believe me, if I had found anything remotely looking like I could stick an OBDII code reader in it, I would have long ago. If you don't like pulling a fuse, just detach the (-) side of the battery for 30 sec; that'll reset everything too.

 

Bob

[Ken H.]

What Mitch said.

 

BMW bike engine management computers do not use the ODB-II standard. Still don't. Even on the new R1200XX hexheads.

[JamesW]

I did something out of character, I read the owners manual on my '04RT and right there in the section that talks about battery removal and replacement is a note that says fault codes will be lost when battery is disconnected and that after re-connect one should turn on ignition switch and roll throttle from min to max a couple of times. Well, fuse F5 is the one that supplies 12 volts to the motronics so it is safe to assume that pulling F5 has the same affect as removing the battery so pull F5 to reset the fault code register. Also, the motronic in all RTs up to '04 cannot be uploaded or programmed. The mapped programs are stored in firmware and changing code plugs simply selects which pre-stored program the motronic computer will run. The motronic has various inputs from sensors like the oxygen sensor, oil temp sensor, elevation sensor and whatever sensor and uses these inputs to adjust the timing and fuel mixture to satisfy the parameters of the program that is preselected by whatever code plug is installed. If a fault should occur to one of the monitored components like the oxygen sensor then a code is stored in the fault code register and depending on the fault, the motronic may switch to a default program that is basic with no sensor inputs so as to enable the motorcycle to be ridden home or to a repair facility. Really pretty simple when you think about it. I believe the computers on the new 1200 machines are more sophisticated in that a technician can actually upload information and change operating parameters. Might be handy to help solve conditions like surging. The tech could maybe richen the mixture slightly for mid range RPMs or maybe adjust timing slightly to reduce pinging. Can't be done to the 1150s since firmware is not software. Oh, and forget a blinking LED code reader because I'll bet that the output from the fault register is all serial data that outputs very fast to a shop computer. Maybe the earlier R1100s fault data could be read watching a blinking LED I don't know. End of motronic theory of operation according to jammess.