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For 1990-2009 cars only
Makes 🢒 Cadillac 🢒 2000 🢒 Seville 🢒 Suspension 🢒 Automatic Level Control 🢒 Automatic Level Control System Operation Check

Automatic Level Control System Operation Check w/o F45

Step

Action

Normal Result(s)

Abnormal Result(s)*

1

Turn the ignition ON.

After approximately 35-55 seconds, the air compressor runs for 3-5 seconds.

Important: This action may be overridden by the height sensor if a load has been added or removed from the vehicle.

    • The air compressor cycles on and off frequently. If no air leaks are present, go to Rear of Vehicle Low .
    • The air compressor runs excessively. Inspect for a disconnected or damaged air tube or a damaged shock absorber. If OK, go to Rear of Vehicle Low .

2

Add a 136 kg (300 lb) load to the luggage compartment.

After a 17-27 second delay, the air compressor runs and the rear of the vehicle rises to the correct trim height. Refer to Trim Height .
    • The air compressor cycles on and off frequently. If no air leaks are present, go to Rear of Vehicle Low .
    • The air compressor runs excessively. Inspect for a disconnected or damaged air tube or a damaged shock absorber. If OK, go to Rear of Vehicle Low .

3
  1. Turn the ignition OFF.
  2. Remove the load from the luggage compartment.

After a 17-27 second delay, a hiss of escaping air may be heard, and the rear of the vehicle lowers to the correct trim height. Refer to Trim Height .

The exhaust solenoid does not energize after a 17-27 second delay and the rear of the vehicle remains above the correct trim height. Refer to Rear of Vehicle High .

* Refer to the appropriate symptom diagnostic table for the applicable abnormal result.

Automatic Level Control System Operation Check w/ F45

Step

Action

Normal Result(s)

Abnormal Result(s)*

1
  1. Turn the ignition ON with the engine off.
  2. Clear the CVRSS DTCs. Refer to Clearing DTCs .
  3. Inspect for CVRSS DTCs using the On-Board Diagnostics. Refer to Displaying Diagnostic Trouble Codes (DTC) .

No CVRSS DTCs are present.

One of the following DTCs is displayed as HISTORY or CURRENT:

    • C0657
    • C0658
    • C0662
    • C0663
        If one of the above DTCs is displayed, go to the appropriate diagnostic table.

2

Turn the ignition ON.

After a delay, the air compressor runs for 3-5 seconds.

Important: This action may be overridden if a load has been added or removed from the vehicle.

    • The air compressor cycles on and off frequently. If no air leaks are present, go to Rear of Vehicle Low .
    • The air compressor runs excessively. Inspect for a disconnected or damaged air tube or a damaged strut. If OK, go to Rear of Vehicle Low .

3

Add a 136 kg (300 lb) load to the luggage compartment.

After a delay, the air compressor runs and the rear of the vehicle rises to the correct trim height. Refer to Trim Height in Suspension General Diagnostics.
    • The air compressor cycles on and off frequently. If no air leaks are present, go to Rear of Vehicle Low .
    • The air compressor runs excessively. Inspect for a disconnected or damaged air tube or a damaged strut. If OK, go to Rear of Vehicle Low .

4
  1. Turn the ignition OFF.
  2. Remove the load from the luggage compartment.

After a delay, a hiss of escaping air may be heard, and the rear of the vehicle lowers to the correct trim height. Refer to Trim Height in Suspension General Diagnostics.

The exhaust solenoid does not energize after a 17-27 second delay and the rear of the vehicle remains above the correct trim height. Refer to Rear of Vehicle High .

* Refer to the appropriate symptom diagnostic table for the applicable abnormal result.