How do I tell if my BCM is Going bad? I have a 2000 convertible and on two different occasions (driving more than 40 miles) I get a message to Service my TPMS system, I reset this and check tire pressures and they vary any where from no pressures to showing 1 or 2 indicated reading on DIC. I also noticed that at that point my Key FOB’s no longer operate. Car runs fine and all other functions on DIC appear to work properly. When I got home I attempted to relearn my FOB ( this worked the first time this problem arose last week) but this time no luck, I checked the 3 BCM fuses and all appeared clean and fine. Now confusingly I was able to relearn the FOB. During this problem the seat memory function also does not work. After FOB reset all works fine. Last week when this happened and I reset the FOB everything worked fine driving around town . Is replacing the BCM DYI project or do you need special tools.

Just went thru the years of the Sticky Section on Electrical. Is the BCM ground found in the passenger side doorpost. All the other Grounds I can locate all appear very clean, will take apart and clean tomorrow. This is the only information I could find in all the years of reading the Sticky. PLEASE HELP

 

Your FOB and TMPS is "speaking" to the Remote Control Door Lock Receiver . This unit is speaking to the BCM using the serial line .
Both units are connected to the splicepoint SP208 . SP208 is connected to ground G104.

SP108 is located above the BCM as shown in the photo below.

I don't think the BCM is causing these problems

 

oelarse, Thank you for the response. G104 was good, I will have to find and check SP 208

 

How old are the wheel senders? The wheel sender batteries begin to fail at around ten years.

 

jim993, I believe the wheel sensors are original ( I have a new set to install). Would these failing cause the other problems, such as the FOB?
Everything works fine after I reset the FOB, TPMS gives proper reading for each wheel until I have driven about 40 highway miles then it all
craps out again. Around town driving does not seem to effect this. This has occurred 3 times that is why I question about the BCM.
Maybe with the G104 ground being close to the headers there might be enough heat expansion to interrupt the ground, but I do not know how to check that.

 

Traction control button or wiring under the arm rest I would look there . I found a open wire setting theses codes off. I got lucky a p1626 was related to it being the open wire was the fuel door popper . Sometimes these wires can run wear . It’s worth a look

 

Speedy007 Thanks I will look there.