I was called out today to a local garage customer to help solve an issue with his 2001 BMW E46 that he had purchased, he was having issues with the cruise control light stuck on and cruise control function not working, other faults also included the trip information in the digital display not working, the only read out the car had was time, you couldn’t scroll through and select MPG or trip distance etc.
Before I got involved the customer had already sent the dash / ECU away and had it checked and the company checking it had come to the conclusion that there was an internal fault, upon receiving this information the customer purchased a new dash but the faults remained.
I plugged my Delphi DS150E in to the car and performed a global scan and a few faults where presented, 1 was a steering angle fault (indicated by the yellow triangle with arrow round on the dash) , there where various other faults that manly related to the battery going flat at some point and we also had a fault code in the instrument cluster 8c Terminal R fault which was a current stored code in the ECU and wouldn’t clear.
First of all I dealt with the steering angle fault and re-calibrated the steering angle sensor using the Delphi and the light went off and I cleared the fault out of the ECU. Now to try and deal with the cruise control problem and the missing info in the trip computer.
Neither issues where bringing up a fault code so where unlikely to be at fault so the fault must have been else where. Through live data I checked the cruise control buttons on the steering wheel and could see that the switches where working fine as we could read the on/off information from the ECU.
So what was this 8c Terminal R fault? this must have something to do with the problems, but where??
After a bit of thought and a bit of reading up, I found that the Terminal R fault relates to a problem with a below 12v supply being fed to the dash, first place to check was the fuse box, fuse number 10 relates to the cruise control and trip info on the dash and guess what!!! the fuse was missing, replaced the fuse on the board turned the ignition on and hey presto, cruise control light was no longer stuck on and we could select through all of the options on the trip computer. A quick scan back in the instrument cluster and erase the terminal R code and the BMW is now working fine and the dash is no longer lit up like a Christmas tree.
I believe the garage will be phoning the company that tested the original dash to find out how they came to the conclusion that it was fried when it wasn’t the problem in the first place.
Ian Burt
Motor Serv Garage Equipment
www.msge.co
Motor Serv Garage Equipment 