Circuit Description WO/F45
The automatic level control (ALC) adjusts the vehicle suspension ride height. The rear integration module (RIM) determines the height of the vehicle based on the voltage from the ALC sensor. The RIM grounds the compressor relay and the exhaust control solenoid to raise and lower the vehicle in order to keep the vehicle level.
DTC Descriptor
This diagnostic procedure supports the following DTC:
DTC C0658 Level Control Compressor Circuit High
Conditions for Running the DTC
| • | The RIM is powered up. |
| • | DTCs B1328 and B1327 are not stored. |
Conditions for Setting the DTC
The compressor relay output is found to be shorted to battery for 10 seconds.
Action Taken When the DTC Sets
The ALC will be inoperative.
Conditions for Clearing the MIL/DTC
The RIM does not detect a failure during the self test.
Diagnostic Aids
| • | Inspect all wiring harnesses carefully for chaffs and proper routing. |
| • | This circuit is monitored during every functional operation of the compressor relay output and every 3.3 milliseconds when output is active. If a compressor relay fault is detected, the RIM retries the output every 15 seconds to try to recover form the fault. |
Test Description
The numbers below refer to the step numbers on the diagnostic table.
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Listen for an audible click when the level control compressor relay operates. Command both the ON and OFF states. Repeat the commands as necessary.
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This step tests for voltage at the coil side of the level control compressor relay. The ELC fuse supplies power to the coil side of the level control compressor relay.
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This step verifies that the RIM is providing ground to the level control compressor relay.
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This step tests if ground is constantly being applied to the level control compressor relay.
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This step tests for a short to voltage.
Step | Action | Yes | No |
|---|---|---|---|
Schematic Reference: Automatic Level Control Schematics | |||
1 | Did you perform the Diagnostic System Check - Vehicle? | Go to Step 2 | Go to Diagnostic System Check - Vehicle in Vehicle DTC Information |
Does the level control compressor relay turn ON and OFF with each command? | Go to Diagnostic Aids | Go to Step 3 | |
Does the test lamp illuminate? | Go to Step 4 | Go to Step 10 | |
Does the test lamp turn ON and OFF with each command? | Go to Step 8 | Go to Step 5 | |
Does the test lamp remain illuminated with each command? | Go to Step 7 | Go to Step 6 | |
Test the control circuit of the level control compressor relay for a short to voltage. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 13 | Go to Step 9 | |
7 | Test the control circuit of the level control compressor relay for a short to ground. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 13 | Go to Step 9 |
8 | Inspect for poor connections at the level control compressor relay . 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 13 | Go to Step 11 |
9 | Inspect for poor connections at the harness connector of the rear integration module (RIM). 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 13 | Go to Step 12 |
10 | Repair the coil side feed circuit of the level control compressor relay . Refer to Wiring Repairs in Wiring Systems. Did you complete the repair? | Go to Step 13 | -- |
11 | Replace the level control compressor relay. Did you complete the replacement? | Go to Step 13 | -- |
12 | Replace the RIM. Refer to Control Module References in Computer/Integrating Systems for replacement, setup, and programming. Did you complete the replacement? | Go to Step 13 | -- |
13 |
Does the DTC reset? | Go to Step 2 | System OK |
