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Does anyone know of a way to turn VATS off on a P12 PCM using Universal Patcher? I know the P12 xml file has not developed any further. I build a 2nd generation Atlas 4.2L I6 for my daughters 2006 Envoy and have it set up on an engine stand. I already ran it pm the stand using the P10, which it ran but had weird issues. I do know for a fact that the Atlas 4.2L I6 2nd generation has a redesigned head and a different valve cover. I also know that the VVT Actuator Cam Gear and the cam sensor are different on the 2nd generation from the first-generation Atlas 4.2L I6. So now I need to run it using the P12 yet VATS and setting the PRNDL to NOT PRESENT are my primary issues. I can live with the PRNDL issue if have to, but the VATS issue is going to be a real pain in my ass. I would appreciate any help that anyone can off. Thank you in advance.

What is the OSID?

antus wrote: ↑Sat Jun 14, 2025 12:47 pmWhat is the OSID?

OSID is 12606400.

Try these. The first has VATS Disabled 0x20989 00->01. The second has that as well as VATS Fail Diagnostic Disabled 0x20961 01->00. Both have checksums updated. I am not sure if you need VATs diagnostic disabled as well or not. There is a third VATS mode which allows fail enable as well. If its still not working I'll add that too (its 0x20987 00->01).

antus wrote: ↑Sat Jun 14, 2025 1:17 pm Try these. The first has VATS Disabled 0x20989 00->01. The second has that as well as VATS Fail Diagnostic Disabled 0x20961 01->00. Both have checksums updated. I am not sure if you need VATs diagnostic disabled as well or not. There is a third VATS mode which allows fail enable as well. If its still not working I'll add that too (its 0x20987 00->01).

Thank you, Antus. I appreciate you very much. I'll give it a shot and let you know what happens.

The part of your question about PNRDL NOT PRESENT, what sort of setting is that? Is that like setting trans type to manual? Or is that a DTC you need to set to not trigger MIL? And if so, what code? Some type of shift module?

antus wrote: ↑Sat Jun 14, 2025 2:10 pm The part of your question about PNRDL NOT PRESENT, what sort of setting is that? Is that like setting trans type to manual? Or is that a DTC you need to set to not trigger MIL? And if so, what code? Some type of shift module?

The VATS off worked perfectly Antus. Thank you. It turns out I don't need a PRNDL delete afterall.

The PRNDL NOT PRESENT setting turns off the neutral safety requirement to start. This is a setting available to all the GM PCMs I have used with Jet DST Tuner.

Sadly Jet Tuners does not support the P12 PCM.