PCM Connector C1 Connector End View

Courtesy of GENERAL MOTORS CORP.
Connector Part Information			15357147 (early) 15430221 (late) 56-Way F Micro 64 (BLU)
Pin	Wire Color	Circuit No.	Function
1-2	-	-	Not Used
3	BRN	436	AIR Pump Relay Control
4	DK BLU	473	High Speed Cooling Fan Relay Control
5-7	-	-	Not Used
8	DK GRN/WHT	817	Vehicle Speed Signal
9-10	-	-	Not Used
11	RED/BLK	380	A/C Refrigerant Pressure Sensor Signal
12	PPL	1589	Fuel Level Sensor Signal (Primary)
13-14	-	-	Not Used
15-16	PPL	1807	Class 2 Serial Data (Primary)
17	-	-	Not Used
18	WHT	1310	EVAP Canister Vent Solenoid Control
19	PNK	39	Ignition 1 Voltage
20	ORN	240	Battery Positive Voltage
21	-	-	Not Used
22	DK GRN	83	Cruise Control Inhibit Signal
23	WHT	121	Engine Speed Signal
24-30	-	-	Not Used
31	GRY	2709	5-Volt Reference
32	BLK	2751	Low Reference
33-34	-	-	Not Used
35	BLK	2759	Low Reference
36-37	-	-	Not Used
38	WHT	1390	Off/Run/Crank Voltage
39	GRY	847	Extended Travel Brake Switch Signal
40	-	-	Not Used
41	DK GRN	890	Fuel Tank Pressure Sensor Signal
42	-	-	Not Used
43	GRY	2700	5-Volt Reference
44	DK GRN/WHT	465	Fuel Pump Relay Control (Primary)
45	YEL	447	Starter Relay Coil Control
46	DK GRN	335	Low Speed Cooling Fan Relay Control
47	-	-	Not Used
48	LT BLU/BLK	396	Cruise Control Engaged Signal
49-50	-	-	Not Used
51	PPL	420	TCC Brake Switch/Cruise Control Release Signal
52	YEL	5	Crank Voltage
53	PNK/WHT	1101	Damping Lift/Dive Signal
54	-	-	Not Used
55	BRN/WHT	419	MIL Control
56	DK GRN/WHT	459	A/C Compressor Clutch Relay Control