Body Control Module (BCM) C1

Courtesy of GENERAL MOTORS CORP.
Connector Part Information		12160778 24-Way F Micro-Pack 100 Series (BRN)
Pin	Wire Color	Circuit No.	Function
A1	BLK	1850	Ground
A2	ORN	1140	Battery Positive Voltage
A3	WHT	194	Door Unlock Control (w/ AU3)
A4	LT BLU	195	Door Lock Control (w/ AU3)
A5-A6	-	-	Not Used
A7	BLK	755	RAP Relay Coil Control
A8	DK BLU	1393	Interior Lamp Relay Coil Control
A9	BLK	28	Horn Relay Control
A10	YEL	1977	Rear Fog Lamp Relay Control (w/ Rear Fog Lamps)
A11	LT GRN/BLK	592	DRL Relay Control (w/ ZR2)
A12	LT GRN	1037	BCM Class 2 Serial Data
B1	BLK	1850	Ground
B2	PNK	39	Ignition 1 Voltage
B3	RED/WHT	812	12 Volt Reference
B4	ORN	461	GMCM Serial Data Signal (w/ AU3)
B5	-	-	Not Used
B6	LT BLU/WHT	1414	Left Front Turn Signal Switch Signal
B7	DK BLU/WHT	1415	Right Front Turn Signal Switch Signal
B8	-	-	Not Used
B9	BRN	41	Ignition 3 Voltage
B10	LT BLU	1134	Park Brake Switch Signal
B11	BLK/WHT	238	Seat Belt Switch - Left
B12	LT BLU	553	Tow/Haul Switch Signal (w/ Floor Shift A/T)

Body Control Module (BCM) C2

Courtesy of GENERAL MOTORS CORP.
Connector Part Information		12110206 24-Way F Micro-Pack 100 Series (LT BLU)
Pin	Wire Color	Circuit No.	Function
A1	YEL	710	Class 2 Serial Data
A2	ORN/BLK	1057	Low Reference
A3	GRY/BLK	690	Courtesy Lamp Relay Control
A4	LT GRN	1391	Driver Door Unlock Relay Control (w/ AU3)
A5	WHT	1080	Park Lamp Relay Control
A6	LT BLU	1344	Lift Glass Relay Output - Coil (Utility)
A7	DK GRN/WHT	1317	Front Fog Lamp Relay Output - Coil (w/ ANL)
A8-A10	-	-	Not Used
A11	WHT	352	Headlamp Relay Coil Supply Voltage
A12	PPL/WHT	1382	LED Dimming Signal
B1	DK GRN/WHT	817	Vehicle Speed Signal
B2	-	-	Not Used
B3	YEL	1836	Security System Sensor Signal
B4	-	-	Not Used
B5	PPL	524	Headlamp Dimmer Switch Signal - High Beam
B6	BRN	2409	Interior Park Lamps Supply Voltage
B7-B8	-	-	Not Used
B9	LT GRN	80	Key-in-Ignition Switch Signal
B10	PNK/BLK	1303	Liftglass Ajar Switch Signal (Utility)
B11	DK BLU/WHT	727	Secondary Door Latch Switch Signal
B12	ORN	1732	Courtesy Lamps Supply Voltage

Body Control Module (BCM) C3

Courtesy of GENERAL MOTORS CORP.
Connector Part Information		12191375 16-Way F Micro-Pack 100 Series (PPL)
Pin	Wire Color	Circuit No.	Function
A1	-	-	Not Used
A2	DK BLU/WHT	1495	Courtesy Lamp Switch Signal
A3	BRN	1356	Flash-to-Pass Switch Signal
A4	GRY	705	5-Volt Reference
A5	GRY	1220	Instrument Panel Lamp Fuse Supply Voltage 2
A6	WHT	278	Ambient Light Sensor Signal
A7-A8	-	-	Not Used
B1	BLK	1576	Lift Glass Release Switch Signal (Utility)
B2	ORN	54	Front Door Jamb Switch Signal - Passenger/Front Door Handle Switch Input
B3	LT GRN	262	Driver Door Key Switch Signal (Domestic Except Base Pickup)
B4	TAN	126	Door Open Switch Signal
B5	ORN	192	Front Fog Lamp Switch Signal (Domestic w/ Front Fog Lamps)
B6	PPL	328	Interior Lamp Defeat Switch Signal
B7	LT BLU	187	Rear Fog Lamp Switch Signal (Export)
B8	PPL/WHT	549	Headlamp Switch - Headlamps Off Signal

When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

• You smell fuel, burning insulation, or see smoke.

• Brakes feel soft, pull hard to one side, or make grinding noises.

• The engine overheats, stalls repeatedly, or misfires under load.

• You are missing required tools, torque specs, or safe lifting equipment.

• You are not confident in the next step or safety outcome.

Safety Warning

Body Control Module (BCM) Connector End Views