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PCM Connector: Grey (C3) 1996-1997
To navigate to a different PCM connector, use the links below:
| C3 (Grey) PCM 32 Pin Connector | ||
|---|---|---|
| Pin | Wire Color | Description |
| 1 | --- | Empty |
| 2 | --- | Empty |
| 3 | --- | Empty |
| 4 | Black | Engine Coolant Temp (ECT) and Throttle Position Sensor (TPS) Ground |
| 5 | --- | Empty |
| 6 | Red w/ Black stripe | PCS High |
| 7 | Dark Blue w/ White stripe | Input Speed Sensor Low (4L80-E Transmission Only) |
| 8 | Red w/ Black stripe | Input Speed Sensor High |
| 9 | White | Ignition Control (IC) Module Control |
| 10 | --- | Empty |
| 11 | Red | Range Signal C (Automatic Transmission Only) |
| 12 | Grey | Throttle Position Sensor 5V Reference |
| 13 | Brown w/ White stripe | Clutch Signal (Manual Transmission Only) |
| 14 | --- | Empty |
| 15 | Brown | EVAP Canister Purge Diagnostic Vacuum Switch Signal |
| 16 | Light Blue w/ White stripe | PCS Low (Automatic Transmission Only) |
| 17 | Black w/ White stripe | System Ground |
| 18 | Black w/ White stripe | Ground |
| 19 | Black | IAT/MAP/EGR Sensor Ground |
| 20 | --- | Empty |
| 21 | Orange | 12 V Battery Feed |
| 22 | Dark Blue | Range Signal B |
| 23 | Pink | Range Signal A |
| 24 | --- | Empty |
| 25 | Dark Green w/ White stripe | A/C Request Signal |
| 26 | --- | Empty |
| 27 | Grey | EGR/MAP 5 Volt Reference |
| 28 | --- | Empty |
| 29 | --- | Empty |
| 30 <-> | Dark Green | A/C Compressor Cycling Switch (1997 only) |
| 30 <-> | --- | Empty (1996 only) |
| 31 | --- | Empty |
| 32 | --- | Empty |
Safety Precautions
Here are some very important safety precautions when testing the wires coming out of the PCM connectors.
- If one or any of the wires on your GM vehicle DO NOT match the color stated in the Pin Out Charts, then you should not use the Pin Out charts in this article. Why? Because this is the clearest indication that these ARE NOT the Connector Pin Out Charts for your particular vehicle.
- Never probe the front of the connector.
- You should use a wire piercing probe and probe the wire a few inches away from the connector.
- To see what this tool looks like: Wire Piercing Probe.
- You should use a back probe.
- You should use a wire piercing probe and probe the wire a few inches away from the connector.
- This is a FLASH unit and requires reprogramming if replaced with a new one or used one.
- Read the Disclaimer.
