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HOMESERVICE MANUALSCHEVROLET2003TRAILBLAZER 4.2 S, 4WDREPAIR AND DIAGNOSISEXTERNAL PAGESDIFFERENT CARSECTION 1426 (WIRING SYSTEMS (COMPONENT LOCATOR))ELECTRICAL CENTER IDENTIFICATION VIEWSFUSE BLOCK - REAR, BOTTOM VIEW

2003 Chevrolet TrailBlazer 4.2 S, 4WD

Fuse Block - Rear, Bottom View

2003 Chevrolet TrailBlazer 4.2 S, 4WDSECTION Fuse Block - Rear, Bottom View

WARNING: This page does not describe the selected car, but rather 6 other vehicles, including the 2004 Oldsmobile Bravada, 2004 GMC Envoy XUV, 2004 GMC Envoy XL, 2004 GMC Envoy, and 2004 Chevrolet TrailBlazer. However, it is still accessible from the selected car via links, so may be relevant.

Fig 1: Fuse Block - Rear, Bottom View

Courtesy of GENERAL MOTORS CORP.

Fuse Block - Rear C1

Courtesy of GENERAL MOTORS CORP.
Connector Part Information		15319896 68-Way F Metri-Pack 280 Series Flexlock (BK)
Pin	Wire Color	Circuit No.	Function
A1	-	-	Not Used
A2	BN/WH	230	Instrument Panel Lamps Dimming Control
A3	-	-	Not Used
A4	L-GN	24	Backup Lamp Supply Voltage (Z88)
A5	-	-	Not Used
A6	BN	4	Accessory Voltage
A7	YE	143	Accessory Voltage
A8	BN	341	Ignition 3 Voltage
A8	BN	341	Ignition 3 Voltage
A9	L-GN/BK	735	Ambient Air Temperature Sensor Signal (CJ3)
A10	PU/WH	1382	LED Dimming Signal (NW7)
A11-A12	-	-	Not Used
B1	L-BU	1134	Park Brake Switch Signal
B2	BN/WH	230	Instrument Panel Lamps Dimming Control
B3	BN	2309	Front Park Lamps Supply Voltage
B4	WH	17	Stop Lamp Switch Signal
B5	L-BU	1320	Stop Lamp Supply Voltage
B5	L-BU	1320	Stop Lamp Supply Voltage
B6-B7	-	-	Not Used
B8	BN	341	Ignition 3 Voltage
B8	BN	341	Ignition 3 Voltage
B9	-	-	Not Used
B10	PU/WH	1382	LED Dimming Signal
B10	PU/WH	1382	LED Dimming Signal (NP8)
B11-B12	-	-	Not Used
C1	OG	4340	Battery Positive Voltage
C1	OG	4340	Battery Positive Voltage (All Except SWB w/CJ3)
C2	-	-	Not Used
C3	BN	2309	Front Park Lamps Supply Voltage
C4	L-BU	2114	Left Turn Signal Lamps Supply Voltage
C4	L-BU	2114	Left Turn Signal Lamps Supply Voltage
C5	YE	685	Left Turn Signal Flasher Signal
C8	BN	341	Ignition 3 Voltage
C8	BN	341	Ignition 3 Voltage
C9-C12	-	-	Not Used
D1	OG	340	Battery Positive Voltage
D1	OG	340	Battery Positive Voltage
D2	-	-	Not Used
D3	BN	2109	Trailer Park Lamps Supply Voltage
D4	D-BU	2115	Right Turn Signal Lamps Supply Voltage
D4	D-BU	2115	Right Turn Signal Lamps Supply Voltage
D5	TN	686	Right Turn Signal Flasher Signal
D8	BN	141	Ignition 3 Voltage (CJ3)
D9	OG	300	Ignition 3 Voltage
D10	BK	481	Outside Moisture Sense Signal 1
D11	-	-	Not Used
D12	PK	39	Ignition 1 Voltage
E1-E2	-	-	Not Used
E3	OG	1040	Battery Positive Voltage
E4	-	-	Not Used
E5	BN	341	Ignition 3 Voltage
E5	BN	341	Ignition 3 Voltage
E6	WH	1390	Off/Run/Crank Voltage
E7	PK	1020	Ignition 0 Voltage
E8	BN	241	Ignition 3 Voltage
E8	BN	241	Ignition 3 Voltage (NP8)
E9	-	-	Not Used
E10	BN	718	Low Reference (CJ3)
E11	-	-	Not Used
E12	PK	639	Ignition 1 Voltage
F1-F2	-	-	Not Used
F3	OG	1040	Battery Positive Voltage
F3	OG	1040	Battery Positive Voltage (Z88)
F4	PK	1020	Ignition 0 Voltage (SWB Export Only)
F5	BN	341	Ignition 3 Voltage (X88/Z88 w/CJ2&NW7)
F6-F7	-	-	Not Used
F8	BN	441	Ignition 3 Voltage
F9-F12	-	-	Not Used

Fuse Block - Rear C2

Courtesy of GENERAL MOTORS CORP.
Connector Part Information		15319894 68-Way F Metri-Pack 280 Series Flexlock (WH)
Pin	Wire Color	Circuit No.	Function
A1	OG	3640	Battery Positive Voltage
A2	BN/WH	230	Instrument Panel Lamps Dimming Control
A2	BN/WH	230	Instrument Panel Lamps Dimming Control
A3	OG	1340	Battery Positive Voltage
A4	-	-	Not Used
A5	OG	2740	Battery Positive Voltage (AR9, Except XUV)
A6	OG	3940	Battery Positive Voltage (XUV)
A7	-	-	Not Used
A8	OG	1240	Battery Positive Voltage
A9	D-GN	1188	Power Window Switch Right Rear Down Signal
A10-A11	-	-	Not Used
A12	L-GN/BK	748	Right Rear Door Ajar Switch Signal
B1	RD	122	Rear Fog Lamp Supply Voltage (T79)
B2	L-BU	1320	Stop Lamp Supply Voltage
B3	OG	1340	Battery Positive Voltage
B4	D-BU	2115	Right Turn Signal Lamps Supply Voltage
B4	D-BU	2115	Right Turn Signal Lamps Supply Voltage
B5	OG	2740	Battery Positive Voltage (Except XUV)
B6	OG	2640	Battery Positive Voltage (XUV)
B7	-	-	Not Used
B8	OG	1240	Battery Positive Voltage
B9-B11	-	-	Not Used
B12	YE	1187	Power Window Switch Left Rear Down Signal (XUV)
C1	OG	3540	Battery Positive Voltage (AR9)
C2	L-BU	1320	Stop Lamp Supply Voltage
C3	L-BU	2114	Left Turn Signal Lamps Supply Voltage (Except XUV)
	L-BU	2114	Left Turn Signal Lamps Supply Voltage (Except XUV)
	OG	2740	Battery Positive Voltage (XUV)
C4	-	-	Not Used
C5	OG	4440	Battery Positive Voltage (Except XUV)
C5	OG	2540	Battery Positive Voltage (XUV)
C6-C9	-	-	Not Used
C10	OG	4140	Battery Positive Voltage
C11	-	-	Not Used
C12	L-BU	2265	Power Window Lockout Left Rear Signal
D1	OG	3540	Battery Positive Voltage (AR9)
D2	BN	2509	Left Rear Park Lamps Supply Voltage
D3	OG	2740	Battery Positive Voltage (XUV w/AR9)
D4	-	-	Not Used
D5	OG	3740	Battery Positive Voltage
D8	TN	294	Door Lock Actuator Unlock Control
D8	TN	294	Door Lock Actuator Unlock Control
D9	-	-	Not Used
D10	OG	4240	Battery Positive Voltage
D11	-	-	Not Used
D12	L-GN	2266	Power Window Lockout Right Rear Signal
E1	OG	840	Battery Positive Voltage (LWB Except XUV)
E1	OG	2440	Battery Positive Voltage (XUV)
E2	BN	2509	Left Rear Park Lamps Supply Voltage
E3	-	-	Not Used
E4	OG	3140	Battery Positive Voltage (UE1)
E4	OG	3140	Battery Positive Voltage (UE1)
E5	L-GN	24	Backup Lamp Supply Voltage (X88,Z70,W49)
	L-GN	24	Backup Lamp Supply Voltage (X88,Z70,W49)
	OG	3340	Battery Positive Voltage (XUV)
E6	L-BU	2114	Left Turn Signal Lamps Supply Voltage (XUV)
E6	L-BU	2114	Left Turn Signal Lamps Supply Voltage (XUV)
E7	D-GN	1488	Noise Reduction Microphone Supply Voltage (UQA w/Class 2 Amp)
E8	L-GN/BK	1354	Drain Wire (UQA w/Class 2 Amp)
E9	YE	1187	Power Window Switch Left Rear Down Signal (Except XUV)
E9	D-BU	5601	Midgate Relay Coil Control (XUV)
E10	OG	2040	Battery Positive Voltage (XUV)
E11	-	-	Not Used
E12	GY/BK	1186	Power Window Switch Right Rear Up Signal
F1	YE	820	CHMSL Supply Voltage
F2	BN/WH	2609	Right Rear Park Lamps Supply Voltage
F2	BN/WH	2609	Right Rear Park Lamps Supply Voltage (Y92)
F3-F5	-	-	Not Used
F6	GY	295	Door Lock Actuator Lock Control
F6	GY	295	Door Lock Actuator Lock Control
F7	-	-	Not Used
F8	BK	1350	Ground
F9	-	-	Not Used
F10	L-BU/BK	747	Left Rear Door Ajar Switch Signal
F11	-	-	Not Used
F12	WH	1185	Power Window Switch Left Rear Up Signal

Fuse Block - Rear C3

Courtesy of GENERAL MOTORS CORP.
Connector Part Information		15319893 32-Way F Metri-Pack 280 Series Flexlock (GY)
Pin	Wire Color	Circuit No.	Function
A1	-	-	Not Used
A2	BK	1350	Ground (Except XUV)
A3	-	-	Not Used
A4	OG	3440	Battery Positive Voltage (XUV)
A5	D-BU	2307	Passenger Air Bag On Indicator Control (Except XUV)
A6	-	-	Not Used
B1	D-GN	1488	Noise Reduction Microphone Supply Voltage
B2	D-GN	801	RAP Fuse Supply Voltage (LWB Except XUV w/CF5)
B3	L-GN/BK	1354	Drain Wire
B4	D-BU	1353	RAP Supply Voltage (SWB w/CF5)
B5	-	-	Not Used
B6	GY/BK	690	Courtesy Lamp Low Control
B6	GY/BK	690	Courtesy Lamp Low Control (Y92)
C1	D-GN	2308	Passenger Air Bag Off Indicator Control (Except XUV)
C1	D-BU	2307	Passenger Air Bag On Indicator Control (XUV)
C2	D-GN	801	RAP Supply Voltage (LWB Except XUV)
C3-C4	-	-	Not Used
C5	BK	1350	Ground (XUV)
C6	-	-	Not Used
D1	-	-	Not Used
D2	D-GN	2308	Passenger Air Bag Off Indicator Control (XUV)
D3-D4	-	-	Not Used
D5	D-BU	1353	RAP Supply Voltage (XUV)
D5	D-BU	1353	RAP Supply Voltage (XUV w/CF5)
D6	L-GN	24	Backup Lamp Supply Voltage
E1	OG	3140	Battery Positive Voltage
E1	OG	3140	Battery Positive Voltage (U42 w/o UG1)
E2	PK	639	Ignition 1 Voltage (DD7/DF5)
E3	BN/WH	230	Instrument Panel Lamps Dimming Control
E4	OG	1740	Battery Positive Voltage (CF5)
E5	-	-	Not Used
E6	BN	718	Low Reference
F1	YE	443	Accessory Voltage (CE1)
F2	-	-	Not Used
F3	L-GN/BK	735	Ambient Air Temperature Sensor Signal
F4	BK	481	Outside Moisture Sensor Signal 1 (CE1)
F5	-	-	Not Used
F6	OG	1732	Courtesy Lamps Supply Voltage
F6	OG	1732	Courtesy Lamps Supply Voltage (Y92)

Fuse Block - Rear C4

Courtesy of GENERAL MOTORS CORP.
Connector Part Information		15077187 40-Way M Flat Wire
Pin	Wire Color	Circuit No.	Function
A1	FW	2140	TBC 2 Fuse
A2	FW	2140	TBC 2 Fuse
A3	FW	748	Right Rear Door Ajar Switch Signal
A4	FW	1134	Park Brake Switch Signal
A5	FW	195	Door Lock Relay Control
A6	FW	2265	Power Window Lockout Left Rear Control
A7	-	-	Not Used
A8	FW	747	Left Rear Door Ajar Switch Signal
A9-A10	-	-	Not Used
A11	FW	1350	Ground
A12	FW	1353	RAP Supply Voltage
A13	FW	194	Door Unlock Relay Control
A14	FW	1080	Park Lamp Relay Control
A15	FW	5168	Power Sounder Enable Signal (BAE)
A16	FW	5204	Intrusion Sensor Data Signal (BAE)
A17	-	-	Not Used
A18	FW	1390	TBC IG Fuse
A19	FW	39	TBC IGN 1 Fuse
A20	FW	541	TBC Run Fuse
B1	FW	230	Instrument Panel Lamps Dimming Control
B2	FW	230	Instrument Panel Lamps Dimming Control
B3	FW	690	Courtesy Lamp Supply Voltage
B4	FW	2240	TBC 3 Fuse
B5	FW	1186	Power Window Switch Right Rear Up Signal
B6	FW	2266	Power Window Lockout Right Rear Signal
B7	FW	1188	Power Window Switch Right Rear Down Signal
B8	FW	1185	Power Window Switch Left Rear Up Signal
B9	FW	1187	Power Window Switch Left Rear Down Signal
B10	-	-	Not Used
B11	FW	1350	Ground
B12	FW	24	Backup Lamp Supply Voltage
B13	FW	4440	TBC 5 Fuse
B14	FW	1382	LED Dimming Signal
B15	-	543	TBC ACC Fuse
B16	-	-	Not Used
B17	FW	4040	TBC 4 Fuse
B18	FW	1732	Inadvertent Power Courtesy Lamps Supply Voltage
B19	FW	1977	Rear Fog Lamp Relay Control
B20	FW	5362	Not Used

RENDER: 1.0x

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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.