Check engine light on after engine swap - Stays on after disconnected
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Check engine light on after engine swap - Stays on after disconnected
2005 Silverado, did a 4.3L to a 6.0L -- swapped over all wiring and PCM from the 6.0L
Everything runs perfectly fine, the only code it is giving is P0650 which is a malfunction indicator light code. I removed that code from the tune, to see if it would make the light turn off, but the check engine light is still illuminated.
So, thinking it was a problem with the PCM, I went and cut the brown/white wire at pin 46 at the PCM - in theory (I think) this should have turned off the check engine light on the dash, but the dash light stayed illuminated!
I also hooked up a volt meter to the PCM side of pin 46, and the PCM is providing a ground, as if the PCM wants the checking light to be on even though there are no codes present.
Has anyone seen this? It is almost like there are two issues - a ground somewhere on the truck side causing the light to stay on and then an issue with the PCM that is grounding pin 46 when it shouldn't.
Though - Maybe if the truck isn't getting a resistance (or something) from PIN 46 of the PCM it automatically sets off the engine light?????????
Any guidance would be a big help.
Everything runs perfectly fine, the only code it is giving is P0650 which is a malfunction indicator light code. I removed that code from the tune, to see if it would make the light turn off, but the check engine light is still illuminated.
So, thinking it was a problem with the PCM, I went and cut the brown/white wire at pin 46 at the PCM - in theory (I think) this should have turned off the check engine light on the dash, but the dash light stayed illuminated!
I also hooked up a volt meter to the PCM side of pin 46, and the PCM is providing a ground, as if the PCM wants the checking light to be on even though there are no codes present.
Has anyone seen this? It is almost like there are two issues - a ground somewhere on the truck side causing the light to stay on and then an issue with the PCM that is grounding pin 46 when it shouldn't.
Though - Maybe if the truck isn't getting a resistance (or something) from PIN 46 of the PCM it automatically sets off the engine light?????????
Any guidance would be a big help.
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Also, I forced the check engine light OFF using HP Tuners scanning software, the PCM still provided a ground to illuminate the check engine light (verified using the volt meter)
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I'll prob tune the original PCM that came with the truck instead of the PCM that came w/ the engine -- plug that in and see what the light does, then move onto the instrument panel and bypass whatever is between the panel and the PCM (run wire straight to PCM)
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I've never heard of IPC codes, I have hptuners scanner and a normal OBD 2 reader, I don't think either read IPC
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The original PCM is from the V6 4.3L. If I hook that up, but do not start the engine - will I damage anything? I would just turn the key to "on" and see if HP Tuners scanner can toggle on/off the check engine light