1996-97 PCM Connector Pin Out Charts (GM 4.3L, 5.0L, 5.7L)

Page 4 of 4

PCM Connector: Black (C4) 1996-1997

To navigate to a different PCM connector, use the links below:

C4 (Grey) PCM 24 Pin Connector
Pin	Wire Color	Description
1	Dark Green w/ White stripe	Fuel Pump Relay Control
2	---	Empty
3	Dark Green w/ White stripe	VSS Output Signal (TCCM, Radio, Cruise)
4	Dark Green	VSS Output Signal (speedometer)
5	Brown w/ White stripe	Malfunction Indicator Light (MIL) Control
6 <->	Dark Blue	Auxiliary Fan Relay (1997 only)
6 <->	---	Empty (1996 only)
7	---	Empty
8	---	Empty
9	---	Empty
10	Purple	Brake Signal
11	Purple	Serial Data
12	---	Empty
13	Brown	12 V Ignition Feed
14	---	Empty
15	Tan w/ Black stripe	Shift Control Lamp
16	---	Empty
17	---	Empty
18	Pink	12 Volt Ignition Feed
19	Black w/ White stripe	4WD Engaged Signal (Automatic Transmission Only)
20	---	Empty
21	---	Empty
22	---	Empty
23	Gray w/ Black	Transfer Case Hi Low Switch
24	Light Blue w/ Black stripe	Cruise Engaged Signal

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.
This is a FLASH unit and requires reprogramming if replaced with a new one or used one.
Read the Disclaimer.