2004 PCM pinout diagram?
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2004 PCM pinout diagram?
I've almost determined that my LS2 swap extension harness for the cam position sensor is wired backwards, but I really want to chase the CMP sensor wiring all the way back to the PCM. Problem is that I can't seem to find a pinout diagram for the 2004 PCM, so I'm not 100% sure which wires are supposed to go where at the PCM. Anybody got a pinout diagram for the 2004? (LS1 CE Coupe MN6, for what it's worth.
Thanks in advance!
Thanks in advance!
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Outstanding! Exactly what I was looking for! Thank you!
I checked the CMP circuits (631, 632, and 633), and they are all good. I thought the red and brown wires were switched, and they are. But further research tells me they are supposed to be switched for converting from LS1 to LS2, so all is as it should be. I will button it all back up with confidence now and move on to other projects.
I checked the CMP circuits (631, 632, and 633), and they are all good. I thought the red and brown wires were switched, and they are. But further research tells me they are supposed to be switched for converting from LS1 to LS2, so all is as it should be. I will button it all back up with confidence now and move on to other projects.
Drifting
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From: New Jersey
You are correct. Many of the connector pinouts are shown, but notably the PCM is missing. Looks like those pages were not copied into the Pdf.
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Running Guns & Moonshine
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Waa the issue resolved?
There is little to no QC with the timing covers / cam sensors for the LS2s from GM. The aftermarket companies are far more reliable with their products and ensuring the correct wires are in the right spot.
The key is to check / verify the dongle on the timing cover connected to the sensor and rigidly installed low to the driver side for accurate wiring assembly. And then just re-pin your adapter loom and likely leave that one on the timing cover alone. Or if it is all off the car, go for it.
There is little to no QC with the timing covers / cam sensors for the LS2s from GM. The aftermarket companies are far more reliable with their products and ensuring the correct wires are in the right spot.
The key is to check / verify the dongle on the timing cover connected to the sensor and rigidly installed low to the driver side for accurate wiring assembly. And then just re-pin your adapter loom and likely leave that one on the timing cover alone. Or if it is all off the car, go for it.
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I don't know yet if the issue is 100% resolved, but I do have a high confidence level now about the CMP sensor wiring from the sensor all the way back to the PCM. The intake is still off, and a new power steering pump is supposed to be showing up tomorrow, so the project will actually get deeper before it gets buttoned up. The EBCM is also throwing codes (has since the beginning since I bought the car), so I'll go ahead and pull it while I'm up there. I've already got the alternator pulled, so I might as well just do it all now. Leaving the intake off forces me to finish the other stuff that needs to be done rather than letting it ride for a little while longer just so I can hear the engine run again. For what it's worth, the labels on the LS2 extension swap harnesses are all dated from August to September of 2019, so the swap and related mods should all have pretty low mileage. I don't think it was driven a whole lot after the swap, because of the column lock messages and the ABS/TC lights being on. I've resolved the column lock, so it's time to do the EBCM fix.
Last edited by vinco; May 19, 2023 at 12:27 AM.