This has been quite a rocky road. It started with the O2 code, I put two new ones in the codes wouldn't clear but the car ran fine. Then it stalled one morning after a bit I installed new pumps the car runs fine but the codes won't clear AND I've got a couple more that won't clear. One pic is before and the other after I tried to clear them.
Any insight would be great.
thanks codes after clearing.jpgcodes before clearing.jpg
Read up on Permanent codes. As I understand it, there are only two ways to clear them. 1. The PCM runs the diagnostic tests that set them in the first place and they pass the test or 2. You reflash the PCM with GM's software and a fresh OS.
I think that I've read that not even #2 will work on some of the newer stuff. But I don't remember how new, and it might not have even GM. Should work on GM gen4.Originally Posted by abc
Do you think I could load in an earlier program and see if that works? I may have the stock tune. I have a buddy that works at a GM dealer that could do it.
It would be really neat if you could POST THE CURRENT TUNE FILE instead of screenshots. Because the answer to your question could go several different ways, depending on if you did something stupid like disabling the codes after they were set, which means if a code can't run its tests then it can never get a 'pass' and will never clear the permanent codes. Maybe the codes didn't get turned off and it simply hasn't been given enough time to pass the diagnostics enough times to self-clear. Or, maybe the reason they haven't cleared is because it's not really fixed yet.
Got all the codes cleared except still have engine light. I loaded the stock tune no codes then put the E tune still no codes but still got the engine light? Maybe it needs to be driven?
Thanks
Well yes it needs to be driven. It may take as many as 20 run cycles during which all the conditions for running the DTC's tests are met and the tests pass (ECT at start, ECT, engine run time, minimum speed, speed within a certain range for a certain amount of time, fuel tank level within a certain range...) before a permanent code self-clears. And different codes can have very different requirements before they'll run.
screenshot.12-02-2025 12.52.19.png
See? A code that's set 'Permanent' WILL NEVER CLEAR if the DTC is disabled ('No Error Reported'), because the tests cannot run. If the tests cannot run and pass a certain number of times, the codes will be there until the heat death of the universe.
Thanks I'll enable them and see what happens.
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