Step | Action | Value(s) | Yes | No |
|---|---|---|---|---|
Schematic Reference: Automatic Level Control Schematics | ||||
1 | Did you perform A Diagnostic System Check - Automatic Level Control? | -- | Go to Step 2 | |
2 |
Does the scan tool indicate that the suspension position sensor is within the specified range? | 0.25-3.0 V | Go to Step 8 | Go to Step 3 |
3 | With the scan tool command the exhaust solenoid open, to vent the system (an audible hiss sound may be heard) . Did the ALC system vent and the vehicle lower? | -- | Go to Step 4 | Go to Step 6 |
4 | Observe the suspension position sensor reading on the scan tool. Did the suspension position sensor reading change more than 1 volt? | -- | Go to Step 8 | Go to Step 5 |
5 |
Important: The vehicle must be raised on a drive on lift. Full vehicle weight must be on the rear tires. Care must be used when disconnecting and retaining the suspension position sensor link. If the link is allowed to travel freely a false DTC may be set.
Did the suspension position sensor reading change more than 1 volt? | -- | Go to Step 8 | Go to Step 9 |
6 |
Important: The vehicle must be raised on a drive on lift. Full vehicle weight must be on the rear tires.
Did the ALC system vent and the vehicle lower? | -- | Go to Step 10 | Go to Step 7 |
7 | Disconnect the air tube assembly from both shock absorbers. Did the vehicle lower? | -- | Go to Step 11 | Go to Step 12 |
8 | Perform the ALC relearn procedure. Refer to Body Control Module (BCM) Programming/RPO Configuration in Body Control System. Did you complete the procedure? | -- | Go to Step 16 | -- |
9 | Inspect for poor connections/terminal tension at the harness connector of the suspension position sensor. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 15 | Go to Step 13 |
10 | Inspect for poor connections/terminal tension at the harness connector of the Automatic Level Control Compressor Assembly. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 15 | Go to Step 14 |
11 | Replace the air tube assembly. Refer to Air Tube Replacement . Did you complete the replacement? | -- | Go to Step 15 | -- |
12 | Replace the shock that did not lower. Did you complete the replacement? | -- | Go to Step 15 | -- |
13 |
Important: Perform the ALC relearn procedure after position sensor replacement. Replace the suspension position sensor. Refer to Automatic Level Control Sensor Replacement . Did you complete the replacement? | -- | Go to Step 15 | -- |
14 | Replace the automatic level control compressor head assembly. Refer to Air Compressor Replacement . Did you complete the replacement? | -- | Go to Step 15 | -- |
15 | Operate the vehicle within the conditions for enabling the automatic level control. Does the ALC operate correctly? | -- | System OK | Go to Step 2 |
16 | Operate the vehicle within the conditions for enabling the automatic level control. Does the ALC operate correctly? | -- | System OK | Go to Step 3 |
