GM Service Manual Online
For 1990-2009 cars only
Figure 1:

Air Compressor (K16), Fuel Tanks and Trailer Connector (RQ2 and U86 or RQ3)


Object Number: 1963774  Size: LF
(1)Splice Pack JX400 (Ground Block)
(2)X409 (8 cavities) Fuel Tank Harness to the Chassis Harness
(3)Fuel Pump (FP) Relay
(4)Fuel Sender - Secondary
(5)Fuel Tank Transfer Pump - Secondary
(6)Trailer Connector (RQ2 and U86 or RQ3)
(7)X410 (3 cavities - K16) Chassis Harness to the Air Compressor Harness
(8)Air Compressor Connector (K16)
(9)Air Compressor Relay (K16)
(10)Air Compressor (K16)
(11)Fuel Sender - Primary
Figure 2:

Air Suspension Dump Valve


Object Number: 1964070  Size: LF
(1)Air Suspension Dump Valve
Figure 3:

Brake Pressure Modulator Valves (BPMV) - Rear


Object Number: 1964312  Size: MF
(1)Brake Pressure Modulator Valve (BPMV) - Left Rear
(2)Brake Pressure Modulator Valve (BPMV) - Right Rear
Figure 4:

Center of Vehicle


Object Number: 1963825  Size: LF
(1)Fuel Pump and Sender Assembly
(2)Primary Fuel Tank
(3)X409
(4)Fuel Sender - Secondary
Figure 5:

ABS Harness to Electronic Brake Control Module (EBCM), Right Side Forward View


Object Number: 239943  Size: LF
(1)Electronic Brake Control Module (EBCM)
(2)EBCM C2
(3)EBCM C1
Figure 6:

Front of Rear Crossmember


Object Number: 1964892  Size: LF
(1)Fuel Tank Transfer Pump - Secondary
(2)Fuel Harness
(3)Fuel Tank Transfer Pump Connector - Secondary
Figure 7:

Fuel Senders, G400, Low Air Alarms, Splice Pack SP400 (Ground Block) - LG4/LG5


Object Number: 1963829  Size: LF
(1)Fuel Sender - Primary
(2)Fuel Tank
(3)Low Air Pressure Switch - Primary
(4)Low Air Pressure Switch - Secondary
(5)Splice Pack JX400 (Ground Block - 6 cavities)
(6)Fuel Sender - Secondary Connector
(7)Ground G400
(8)Fuel Sender - Secondary
(9)Fuel Tank - Secondary
Figure 8:

Fuel Tank Harness, Left Side


Object Number: 1965095  Size: LF
(1)Fuel Sending Unit Connector
(2)Fuel Tank Sender
(3)Fuel Transfer Pump Connector
(4)Fuel Transfer Pump
(5)Back of Cab Crossmember
(6)Fuel Tank Harness
(7)X411
(8)Rear Chassis Harness
Figure 9:

Pressure Modulator Valve (BPMV) - Left Front and Right Front


Object Number: 1964308  Size: LF
(1)Brake Pressure Modulator Valve (BPMV) - Right Front
(2)Brake Pressure Modulator Valve (BPMV) - Left Front
Figure 10:

Rear Chassis Harness to Transfer Case


Object Number: 1964055  Size: LF
(1)Transfer Case Crossmember
(2)Transfer Case Encoder Motor Connector
(3)Rear Chassis Harness
(4)Transfer Case Encoder Motor
(5)Transfer Case
Figure 11:

Rear Crossmember


Object Number: 1964889  Size: LF
(1)Fuel Pump Relay - Secondary
(2)X420
(3)X304 (8 cavities - RQ2 and U86 or RQ3)
(4)Heated Oxygen Sensor (HO2S) Bank 2
(5)Heated Oxygen Sensor (HO2S) Bank 1
(6)JX400 (Ground Block - part of the Negative Battery Cable)
(7)Rear Chassis Harness
Figure 12:

Wheel Speed Sensor (WSS) - Right Front, Left Front Similar


Object Number: 1964285  Size: LF
(1)Wheel Speed Sensor (WSS) - Right Front
Figure 13:

Wheel Speed Sensor (WSS) - Left Right, Right Rear Similar


Object Number: 1964296  Size: MF
(1)Wheel Speed Sensor (WSS) - Left Rear
Figure 14:

Wheel Speed Sensor (WSS) - Right Front


Object Number: 1964300  Size: LF
(1)Wheel Speed Sensor (WSS) - Right Front
Figure 15:

Wheel Speed Sensor (WSS) - Left Front


Object Number: 1964303  Size: LF
(1)Wheel Speed Sensor (WSS) - Left Front
Figure 16:

Wheel Speed Sensor (WSS) - Left Rear and Right Rear


Object Number: 1964306  Size: LF
(1)Wheel Speed Sensor (WSS) - Left Rear
(2)Wheel Speed Sensor (WSS) - Right Rear