There's not water inside the cab is there?
2010 Cobalt LT flashing driving lights
- Thread starter roosterk0031
- Start date
roosterk0031
Full Access Member
Never seen any, haven't check antifreeze, but if something was leaking inside I think in 200 miles on Saturday I would have noticed, no antifreeze smell inside either. I haven't driven it in rain, it just barely misting part of Saturday.
I can wash/hose it down in the garage if you think water coming in that way. In slab heating and I have a hose hooked up to it for washing and floor drains to take it away.
All the errors I think point to the BCM, but the wiring harness could be the real cause lack of communication with the ECM.
So options are replace the harness first or wait till it quits and have to have it towed to dealer, as soon as they spot or I point out the harness connector damage they'll likely say they need to replace it first. Harness looks like $200, probably $300 or more at the dealer. Haven't looked at it real close to see how hard to do, starter might be the lowest thing to reach.
I can wash/hose it down in the garage if you think water coming in that way. In slab heating and I have a hose hooked up to it for washing and floor drains to take it away.
All the errors I think point to the BCM, but the wiring harness could be the real cause lack of communication with the ECM.
So options are replace the harness first or wait till it quits and have to have it towed to dealer, as soon as they spot or I point out the harness connector damage they'll likely say they need to replace it first. Harness looks like $200, probably $300 or more at the dealer. Haven't looked at it real close to see how hard to do, starter might be the lowest thing to reach.
The wiring wouldn't cause the button confusion, it uses hex addressing, kinda like a phone number. If I dial 444-444-4440 over a bad line I might miss a digit, but it won't dial 444-444-4441.
I think the BCM might be bad. Wrecking yard is a good place to find one.
I think the BCM might be bad. Wrecking yard is a good place to find one.
roosterk0031
Full Access Member
Kind of my thinking as well, just trying to think like a dealer would. I think all the symptoms/systems affected are controlled by BCM.
Found out a nephew has a spare GM harness he bought to use pieces for his TBSS, going to try to see if I can swap pieces to make the connector look intact.
From what I've read I thought the BCM has to be replaced by the dealer?
Found out a nephew has a spare GM harness he bought to use pieces for his TBSS, going to try to see if I can swap pieces to make the connector look intact.
From what I've read I thought the BCM has to be replaced by the dealer?
I know the ECU needs to be "paired" to the car by a mechanic with a Tech2 system. you can replace it yourself, just won't work until paired. I'm not sure about the BCM.
roosterk0031
Full Access Member
Moved the car out of the garage last night, it's been enjoying the garage since it started for the last 2+ weeks. An experiment to see if I can have her resume driving it I moved it out and put the wife's Impala back in. In the middle of the night neighbor knocks on door, lights are flashing so I disconect the battery. This morning I reconnected and lights resume flashing. As a piece of detective work I place a electric heater on passenger floor pointed towards the BCM. Give it 45 minutes, connect battery no flashing, car starts. Guess it's doesn't like outside. 18 degrees F outside by the car. Time to replace the BCM.
Last edited:
Huh. That's a weird one.
roosterk0031
Full Access Member
Looking back temp seems to always have had a play in it. The first night it was cold, next day (afternoon) when I swapped batteries it was sunny and almost 40. Thanksgiving evening it was single digits. The Sunday it started it was warm enough my mom was washing her van outside.
Well I hope this solves it.
roosterk0031
Full Access Member
Going to deliver to dealer sometime next week when it's cold overnight and disconnect battery so hopefully it will do it for them in the morning. Want to make sure they agreed before just trying parts. Will be getting a quote from them for replacement before I deliver it. If too crazy I'll look around a little more.
