oldred95
February 21st, 2022, 11:34 AM
I'm doing an 0411 swap on a 96 C1500 project. Seems simple enough. I obtained the proper spreadsheet from Lextech and the repinning all seemed to go pretty well. Prior to the swap I took my new to me used 0411 PCM I got off ebay and fabbed up a bench test harness so I could read and save the file and mostly just make sure I didn't receive a brick in the mail. That went perfectly smooth. Once I did the swap and tried to communicate with the PCM things got considerably less smooth. I have no communication. I check my powers and they are correct. The spreadsheet said to pin Class 2 serial data to pin 59 which come to find out isn't wrong, just not right for my application as I'm not using a BCM and pin 58 is actually the Class 2 circuit. Still nothing. I test my grounds. They all match up with what the spreadsheet says with the exception of C1 pin 60. The spreadsheet says that is the TPS and ECT low reference. On my bench test harness that was the ground for the PCM. One of many grounds but evidently the main one to allow it to power up and communicate. This is where I don't know what to do because after countless google searches, every 0411 C1 connector end view I've found says pin 60 is a low reference for one sensor or another and not the PCM ground like it is on the bench test diagram. Can someone shed some light on this for me? If I ground pin 60 I believe I will have communication but where do I take the TPS/ECT low reference that currently resides on pin 60? Thanks for any and all help.