I have a 09 cobalt lt 2.2L with roughly 190k miles on it. Fuel oump went iut about 3 mk ths ago, replaced that and ran great. Wome up to go to work and my car will crank and not start. When I first out an OBD on it, it threw a P1682 (voltage difference between circuits) went and cleaned off all grounds. Verified my battery was good and fully charged. Check alternator and starter, both good. My friend brought his scanner over (so much more in depth than my cheap one). His showed a P1370-06. Short to ground ignition 1. I did the yesy light and fuse thing, no fuse turned the test off. Am going to try with a multimeter next but if that doesnt work, idk wjere to get the wiring schematics for it necause because the 09 cobalt ones are not online for free access. So now i'm at a loss on what to do now. Please help ASAP!
His showed a P1370-06
Are you sure it isn't B1370?
Which module reported this code? BCM or SDM?
Yes sorry!! B1370-06 Ignition 1 circuit short to ground. And before my friend out his scanner on my little cheap one was reading a P0641. I for the life of me can not figure out where to even begin.
Ignition 1 circuit short to ground.
I don't think that's correct.
Yes sorry!! B1370-06
I repeat, it's important to note which module is setting a DTC when you run a diagnostic. The code means different things depending on the module, and you'll need different schematics.
So again, BCM or SDM?
my little cheap one was reading a P0641. I for the life of me can not figure out where to even begin.
You can begin with looking up the code to find out the definition on obd-codes.com
There's also troubleshooting steps there you can follow, but I think it's going to related to the B1370
Make sure the Theft light isn't staying on or blinking.
Then put your finger on the Run/Crank relay ((NOT the Crank relay)) and have somebody turn the Key to RUN.
Can you feel the relay click? If not swap out the relay with a defroster relay or another non critical relay. Repeat.
If the relay still doesn't click troubleshoot the relay sockets with a test light.
There needs to be Battery power at socket 30.
A good Ground at socket 86.
Power at socket 85 with the key in Run or Start.
The next thing would be to check the ignition switch's Ign 1 circuit.
There needs to be Battery power on the Red wire ((Hot at all times))
Battery power on the Yellow wire in Run and Start.
Battery power on the Brown wire in ACC and Run .
(WHT/BLK is the 5 volt reference signal from the BCM.
WHT is the 5 volt signal return to the BCM) ((theft system)).
