Pin outs and wiring for different OS/PCMs?
Thread Starter
Joined: Apr 2003
Posts: 1,631
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From: Macomb, MI
Pin outs and wiring for different OS/PCMs? I'm running into an issue and just looking for a quick answer to my question. I'm wiring up the A/C Compressor and related sensors on my swap vehicle. It is using a 2002 Silverado PCM with a 411 service code. A truck PCM of that year uses a high and low pressure switch, vs a Camaro of the same year that uses a trinary switch. The pinouts for the A/C Systems are obviously different, but I was wondering if the pinouts for the Camaro A/C would work. In the service manuals, the pins are not used at all on the truck harness, so if I just add the pins, would it work, or will the truck OS on the PCM not even recognize something on those pins.
I would just wire it with the truck A/C wiring and sensors, but that would mean I need new lines as the fittings for the sensors are non existent, so I'm trying to keep with the trinary switch if possible and avoid the cost of having bungs welded into the lines.
If anyone has any insight, it would be greatly appreciated.
I would just wire it with the truck A/C wiring and sensors, but that would mean I need new lines as the fittings for the sensors are non existent, so I'm trying to keep with the trinary switch if possible and avoid the cost of having bungs welded into the lines.
If anyone has any insight, it would be greatly appreciated.
I don't know for sure, but I would think that if you flash the Silverado pcm with a Camaro file/operating system, the pinouts for the Camaro style a/c system would work. Is that a viable solution or is there a reason that you would have to stick with the Silverado OS?
You will have to wire it according to the truck diagram using the high and low pressure switches and flash it to a truck o/s. The camaro uses a variable displacement compressor which runs 100% of the time, that is why there is not a cycling switch like the truck uses. The pcm will not recognize the sensors just being wired into the pcm because the compressor cycling strategies built into the programming are completely different between the two vehicles. Your only other option is to flash to a camaro o/s and wire in the 3 wire pressure switch. You can then wire in a cycling switch into the a/c request line from the a/c control panel to properly cycle the a/c clutch.
