Ecm/bcm issues?
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2nd Gear
Joined: Oct 2024
Posts: 2
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Ecm/bcm issues?
Car has 93k miles, owned it for two years never a problem. Went out after work and started car up and every light and error on the dash went off. Some guages went to max and some went to min., windows dont work, headlight only come on manually (no twilight), hatch wont open with FOB or buttom, no FOB funtions at all. Drove the car home with no problems and even thought the reduced engine was displaying the engine ran as normal. Turn car off in garage and now nothing works at all, it wont even turn over. Tried to run codes and all sections come back with the "No Comm." error. Car will still start but only if I take off negative cable then reattach. Had battery tested, replaced negative cable, and then opened both doors, grabbed wires inside accordian tube and shaked them roughly. No luck. Any suggestions?
Melting Slicks
Joined: Sep 2008
Posts: 3,127
Likes: 799
From: Espanola New Mexico
There are two connectors by the BCM which have metal jumpers or combs as their called. This jumpers connect all of the car modules together. You should remove the jumpers and connect a wire between pin M light green wire on one connector and pin B dark green wire of the other connector. Doing this leaves only the BCM and PCM connected and all other modules are disconnected, see if that works because one of the modules may be crashing the seriel data buss. I will add that any time you have to disconnect and reconnect the negative battery cable to get the car to start usually means the BCM is at fault.
Melting Slicks
Joined: Feb 2001
Posts: 2,800
Likes: 356
From: Northville, MI
I had this problem myself two years ago, check everything out from clutch bypass to ignition, to TDR relay to BCM. still had to remove and reattach battery cable to start. cleaned all the ground in the car, problem solved.
Last edited by Gordy M; Nov 6, 2024 at 09:27 AM.
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