I, too, have the 2005 Cobalt demonic possession. While driving, all of these things happen at once and randomly:
Door locks locking up/down
Power steering light replaces odometer reading, sometimes just dashes ----
Speedometer goes to zero, jumps up and down sometimes
Tach jumps up and down
Dinging - crazy dinging
Gears slip (automatic transmission)
Can hear the RPMs go up and down
Air bag warning light, on and off (I am terrified!)
TC light, mostly constant
Bogs down, like it will die
Interior/exterior lights fluctuate
It is the most FRIGHTENING experience! Cannot drive this UNSAFE car. I contacted GM, got a case number. (There's no recall for this, though hundreds of people have this problem. Basically, they don't care.)
The 2005 Cobalt LS sedan (no frills) belongs to my daughter. I don't own a car. She works part-time and is in her senior year of college. We do not have $$ to go to the dealership to get ripped off. I am a computer geek, so I pulled the BCM and took it apart myself. The board looked good. I have checked all fuses to be good. I have cleaned/sprayed and greased the connectors to the BCM, ECM, TCM.
I am not a car mechanic, I'm a mom. But, I am doing everything possible to help my daughter. I have been reading all sorts of fixes (and non-fixes) for about 3 days now.
Coby7, I am starting to try checking all of the ground wires. I am not sure where all of them are, but I do know some. I have a question about this wire that I found below the oil stick. It goes to a black plug. Can you tell me if this pitiful-looking wire might have something to do with the problem? It looks like it has been modified before because it has nasty tape on it. Though it looks wet/oily, it is dry.
(happy to help anyone with computer problems)
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