Instrument Failure, 2004 GS 1200

[big man]

I hope someone can help me with a strange problem with the instruments on my 2004 R1200GS. I first noticed the problem when the needle on the speedometer started to momentarily “dip” intermittently. About 30 miles later this dipping became more frequent as soon as I slowed. At this point I suspected that the rear wheel speed sensor might be an issue and so intended to have a look to see if there were any metal fragments on it when I got home.

However, shortly after this, both the yellow and red warning triangles on the dashboard started to flash, so I stopped the bike to cycle the ignition to see if things would clear. The initial start-up diagnostic ran through OK, so started the bike and carried on. Shortly after this the speedometer dropped to zero and the brake warning lights started to flash. At this point I turned for home, a journey of about 40 miles. As I rode home, the whole of the dashboard became erratic; speedometer and revcounter going to zero, warning lights flashing and the LED display appearing to be going through its re-boot procedure almost constantly.

I ran a scan with my GS 911 when I got home and tested the battery voltage, which was just over 12 volt. As the battery was about 5 years old and had covered about 42,000 miles (about the same as the original) I thought this could be the issue and so bought a replacement Odyessey battery. After fitting this, all seemed ok until about a mile down the road when the symptoms began again. Back home, I removed the tank to check for any problems with electrical connections etc. but did not discover any problems. A full scan with the GS 911 showed no issues, so after fitting the tank I tried a short run, with no problems. That evening I did about 100 miles; again all ok.

The following day, about 50 miles from home and the problem has returned. Once home I ran a scan (attached) which gave error 1028 (CAN-bus timeout, no communication with KOMBI) also 25160 (Internal control module error) and 54087 (Can bus; No communication with any other modules) relating to the ABS module. After leaving the bike for an hour or so, the latest scan shows no present errors (except for fuel pump and level indicator as I have the tank off).

I am currently thinking of replacing the rear speed sensor (although I can’t see how it can cause such catastrophic issues) and wondering if the either the ABS or KOMBI units are shot. Any thoughts would be much appreciated.

Sorry to have been so long winded!

 

[Pukmeister]

Check the small multi-plug at the rear of the instrument panel is fully seated as a first step.

 

[big man]

Tnaks for the reply, Pukmeister.

The plug is fully home and also free from corrosion

 

[Pukmeister]

Sounds like several controllers are not communicating across the network. I think the next step logically would be to check the wiring loom for chafing or damage, and clean the rear wheel speed sensor and check its signal cable for damage. I'm afraid my knowledge of data networks only extends to computers, TCP/IP and data transfer via Modbus not CANBUS so I am not much help, sorry. At the end of the day if I understand it correctly its just a twisted pair signal between the controller modules anyway.

I was gonna suggest battery voltage but you seem to have covered that one (unless you have a charging circuit issue and the voltage is dropping.)

 

[tanneman]

You might have an earth somewhere in the loom. If you have the Hayens manual look at the circuit diagrams at the back. Follow the circuit from the affected modules as per fault code readout till you find a common spot. Look on the bike from that spot onwards for any binding, pinched or chafed loom. If it is only the abs module then follow that loom, you may have to disassemble the loom to trace the fault. You can try to reproduce the fault by moving the loom about then you'll know exactly where the fault is. You can also try to measure the resistance from the pins of the affected module to the controller (ZFE). As the Haynes manual only give the colour coding you'll have to match the wire to the pin, in that case the loom will have to come apart. Just my suggestions, try the simple things first as suggested or ask your mate if you can swap bits between bikes untill the fault goes away. That is if your mate has the same bike as you. Won't do harm to ask on ADVrider.com

 

[Bendy toy]

Also check the battery and charging circuits. Under and over voltage will cause problems.

 

[fizzer]

on the other hand do you know someone with the same bike,you could just try there clocks its only a multiplug and three slide out pins ,worth a try

 

[big man]

Problem Solved

Well, the problem seems to have been solved. After spending four days tracing through the wiring, buzzing out for continuity and checking for anything going to earth which shouldn’t, I ran out of time and had to hand over the bike to my local BMW technician. To cut a long story short he eventually found three frayed wires in the loom in the area of the battery box. Since this damage was repaired I have covered about 250 miles with no problems. If the bike survives a longer distance check at the weekend, I will be heading off for Sardinia and Corsica early next month.

Possible cause of the damage would seem to be my Odyssey battery. This was installed at about 40,000 miles after the original failed. It looks like the larger dimensions have either stretched the wiring or chaffed against it. I hope this information helps someone else if they run into similar issues.

Thanks again for all the input and suggestions.

Dave

 

[Pukmeister]

Thanks for the feedback, alls well that ends well as they say.