WARNING: This page is about a different car, the 2007 Saturn Ion Red Line, 2007 Saturn Ion 3, and 2007 Saturn Ion 2. However, it is still accessible from the selected car via links, so may be relevant.

Fig 1: Body Control Module (BCM) C4 Connector End View

Courtesy of GENERAL MOTORS CORP.

Body Control Module (BCM) C4 Connector & Terminal Parts Information

Connector Part Information

OEM: 1326144-2
Service: See Catalog
Description: 56-Way F Amp (GY)
1241495-2 28-Way F (GY)
1241494-2 28-Way F (BU)

Terminal Part Information

Pins: 1, 2, 4-7, 9, 35, 48-50, 52, 53, 55
Terminal/Tray: 968074-5/17
Core/Insulation Crimp: E/C
Release Tool/Test Probe: 12031876-1/J-35616-4A (PU)

Pins: 47
Terminal/Tray: 968075-5/17
Core/Insulation Crimp: 2/4
Release Tool/Test Probe: 12031876-1/J-35616-4A (PU)

Pins: 11, 12, 23, 43, 44, 45, 13- 20, 22, 27, 29, 30-34, 36, 37, 39, 40-42, 46
Terminal/Tray: 928999-5/15
Core/Insulation Crimp: Pins 11, 12, 23, 28, 43, 44, 45 - J/J
Core/Insulation Crimp: Pins 13-20, 22, 27-29, 30-34, 36, 37, 39, 40, 41, 42, 46 - H/H
Release Tool/Test Probe: 12094429/J-35616-64B (L-BU)

Body Control Module (BCM) C4 Terminal Identification

Pin	Wire Color	Circuit No.	Function
1	RD	228	Windshield Washer Pump Control
2	BN	9	Park Lamp Supply Voltage
3	-	-	Not Used
4	BN	9	Park Lamp Supply Voltage
5	BN	9	Park Lamp Supply Voltage (T82)
6	BN	4	Accessory Voltage
7	D-BU	338	Run/Crank Voltage
8	-	-	Not Used
9	BN/WH	230	Instrument Panel Lamps Dimming Control
10	-	-	Not Used
11	YE	18	Left Turn Signal Lamps Supply Voltage
12	D-GN	19	Right Turn Signal Lamps Supply Voltage
13	GY	8	Instrument Panel Lamps Supply Voltage
14	GY	8	Instrument Panel Lamps Supply Voltage
15	GY	8	Instrument Panel Lamps Supply Voltage
16	GY	8	Instrument Panel Lamps Supply Voltage
17	GY	8	Instrument Panel Lamps Supply Voltage
18	PU	1807	BCM Class 2 Serial Data
19	PU	1807	BCM Class 2 Serial Data
20	PU	1807	BCM Class 2 Serial Data
21	-	-	Not Used
22	L-GN	66	A/C Request Signal (C60)
23	PK/WH	1970	Headlamp Low Beam Relay Control (T82)
24-26	-	-	Not Used
27	BK/WH	151	Ground
28	PU	719	Low Reference
29	GY	8	Instrument Panel Lamps Supply Voltage (UXE)
30	GY	8	Instrument Panel Lamps Supply Voltage
31	GY	8	Instrument Panel Lamps Supply Voltage (T37/T96)
32	YE	317	Fog Lamp Relay Coil Supply Voltage (T37/T96)
33	BK	28	Horn Relay Control
34	BN	323	Shift Lock Solenoid Supply Voltage (A/T)
35	PU	5234	Passenger Seat Belt Indicator
36	WH	193	Rear Defog Relay Control
37	PU/WH	549	Headlamp Switch Headlamps Off Signal (T82)
38	-	-	Not Used
39	PU/WH	1572	Traction Control Indicator Control (NW7)
40	L-BU	1508	Turn/Hazard Switch Supply Voltage
41	GY	112	Windshield Wiper Switch Signal 1
42	BN/WH	1571	Traction Control Switch Signal (NW7)
43	L-BU	1134	Park Brake Switch Signal
44	L-BU	395	Passenger Door Jamb Switch Signal
45	L-GN/BK	394	Driver Door Jamb Switch Signal
46	L-BU	292	Rear Defog Switch Signal
47	D-BU	1201	Headlamp Low Beam Signal
48	WH/BK	1073	5-Volt Reference
49	GY	728	Security Indicator Control
50	L-GN/BK	1137	DRL Ambient Light Sensor Signal 5-Volt (T82)
51	-	-	Not Used
52	OG	192	Front Fog Lamp Switch Signal (T37/T96)
53	WH	1390	Off/Run/Crank Voltage
54	-	-	Not Used
55	YE/BK	1138	DRL Ambient Light Sensor Low Reference (T82)
56	-	-	Not Used

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) C4

Use the Manual With the Right Hardware

When to See a Mechanic

Rather have a pro handle this?