92 Lt1 CCM code C-12 Help..
Thread Starter
3rd Gear
Joined: Jun 2004
Posts: 3
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From: Travis AFB CA
92 Lt1 CCM code C-12 Help..
I have a 92 LT1 6 speed, My display panel had been flashing SYS for several days then finally all my digital displays blacked out. They would return after the vehicle was turned off or the fuses were pulled and reinstalled. This has gone on for about a week. I parked the car for about a month due to a military deployment and when I returned the car runs like crap and puffs out serious black smoke. So, I jumped A-B for ECM fault codes and nothing, so I jump A-G for CCM Codes and the display code was C-12. Does anyone know what C-12 is?
Race Director
Joined: Apr 2000
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From: Texas
Re: 92 Lt1 CCM code C-12 Help.. (Afgolfpro)
I have a 92 LT1 6 speed, My display panel had been flashing SYS for several days then finally all my digital displays blacked out. They would return after the vehicle was turned off or the fuses were pulled and reinstalled. This has gone on for about a week. I parked the car for about a month due to a military deployment and when I returned the car runs like crap and puffs out serious black smoke. So, I jumped A-B for ECM fault codes and nothing, so I jump A-G for CCM Codes and the display code was C-12. Does anyone know what C-12 is?
Kind of sounds like a dying battery.
Thread Starter
3rd Gear
Joined: Jun 2004
Posts: 3
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From: Travis AFB CA
Re: 92 Lt1 CCM code C-12 Help.. (96GS#007)
Thanks, I did change the battery and the display has stayed on and SYS doesn't seem to flash. But the car still seems to be running on 5-6 cylinders. When I parked the car last month it ran fine. Could it be possible for the ECM to be bad without having a fault code?
Race Director
Joined: Apr 2000
Posts: 15,344
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From: Texas
Re: 92 Lt1 CCM code C-12 Help.. (Afgolfpro)
...Could it be possible for the ECM to be bad without having a fault code?
Thread Starter
3rd Gear
Joined: Jun 2004
Posts: 3
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From: Travis AFB CA
Re: 92 Lt1 CCM code C-12 Help.. (96GS#007)
It had over half a tank when I parted it in my garage. I changed the Opti, plugs and wires about 8 months ago after the water pump started leaking and shorted it out. THe only other things that have been done to the car is the clutch was replaced. Thanks for your help, I will post it on the tech page and see what happens.
