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

Below Vehicle, Rear of LR Wheelhouse


Object Number: 447384  Size: LF
(1)Pass Through P403
(2)In-line Connector C407
(3)Auto Level Control Harness
(4)Auto Level Control (ALC) Sensor Connector
(5)Auto Level Control (ALC) Air Compressor
(6)Auto Level Control (ALC) Compressor Relay
(7)Auto Level Control (ALC) Connector
Figure 2:

Underneath Rear of Vehicle


Object Number: 447350  Size: LF
(1)Auto Level Control (ALC) Harness
(2)Auto Level Control (ALC) Sensor
Figure 3:

Behind Rear Left Wheelhouse


Object Number: 447335  Size: LF
(1)Auto Level Control (ALC) Inflator Solenoid Valve
(2)Inflator Air Switch
(3)Body Harness
(4)Rear Electric Accessory Plug Housing
(5)Auto Level Control (ALC) Inflator Relay
(6)Auto Level Control Harness