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For 1990-2009 cars only
Makes 🢒 Buick 🢒 2006 🢒 Terraza - 4WD 🢒 DTC 🢒 DTC 022

Circuit Description

The automatic level control sensor monitors the level control compressor relay coil control circuity for a open circuit or short to battery.

DTC Descriptor

This diagnostic procedure supports the following DTC:

DTC 022 Level Control Compressor Relay Circuit Short to Battery or Open

Conditions for Running the DTC

The ignition is ON.

Conditions for Setting the DTC

This DTC is set when the automatic level control sensor detects the level control compressor relay coil control circuit is open or shorted to battery.

Action Taken When the DTC Sets
    • The automatic level control sensor disables the compressor.
    • Lowering functions shall continue.
    • The automatic level control sensor disables inflator functions.

Conditions for Clearing the DTC

The conditions that caused the DTC to set have been removed.

Diagnostic Aids

A short to battery or an open circuit in the level control compressor relay coil control circuit will set this DTC.

Test Description

The numbers below refer to the step numbers on the diagnostic table.

  1. This step tests for battery positive voltage at the relay coil. The ELC fuse supplies power to the relay coil of the level control compressor relay.

    2.

  2. This step verifies that the automatic level control sensor is providing ground to the level control compressor relay.

    3.

  3. This step tests if battery positive voltage is constantly being applied to the level control compressor relay control circuit or the circuit is open.

    4.

  4. This step verifies that the automatic level control sensor is self tested after replacement.

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

2

  1. Turn ON the ignition.
  2. Disconnect the level control compressor relay.
  3. Probe the battery positive voltage circuit of the level control compressor relay with a test lamp that is connected to a good ground.

Does the test lamp illuminate?

Go to Step 3

Go to Step 7

3

  1. Connect a test lamp between the coil control circuit of the level control compressor relay and the battery positive voltage circuit of the level control compressor relay.
  2. With the accessory inflator switch, command the accessory inflator valve ON and OFF.

Does the test lamp turn ON and OFF with each command?

Go to Step 5

Go to Step 4

4

Test the control circuit of the level control compressor relay for a short to voltage, ground, or an open. Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

Go to Step 10

Go to Step 6

5

Inspect for poor connections at the level control compressor relay. Refer to Testing for Intermittent Conditions and Poor Connections and Wiring Repairs .

Did you find and correct the condition?

Go to Step 10

Go to Step 8

6

Inspect for poor connections at the harness connector of the automatic level control sensor. Refer to Testing for Intermittent Conditions and Poor Connections and Wiring Repairs .

Did you find and correct the condition?

Go to Step 10

Go to Step 9

7

Repair the battery positive voltage circuit of the level control compressor relay coil. Refer to Wiring Repairs .

Did you complete the repair?

Go to Step 10

--

8

Replace the level control compressor relay. Refer to Automatic Level Control Relay Replacement .

Did you complete the replacement?

Go to Step 10

--

9

Important: System untested codes will continue to flash until self test has been completed after automatic level control sensor replacement .

Replace the automatic level control sensor. Refer to Automatic Level Control Sensor Replacement .

Did you complete the replacement?

Go to Step 10

--

10

Operate the vehicle within the Conditions for Running the DTC as specified in the supporting text.

Does the DTC reset?

Go to Step 2

System OK