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Makes 🢒 HUMMER 🢒 2007 🢒 H2 🢒 Driver Information and Entertainment 🢒 Cellular, Entertainment, and Navigation 🢒 DTC C0718

Circuit Description

The air suspension compressor 2 has a temperature sensor. The overtemperature sensor is a thermal limit switch that is in the normally closed position. This provides a ground signal to the air suspension module. The air suspension module monitors the temperature sensor for a compressor overtemperature condition. On receipt of a compressor overtemperature condition the air suspension module switches off the compressor relay. The relay cannot be switched on again until at least 3 minutes after removal of the overtemperature condition.

DTC Descriptor

This diagnostic procedure supports the following DTC:

DTC C0718 Level Control Compressor 2 Overtemperature

Conditions for Running the DTC

The ignition is ON.

Conditions for Setting the DTC

Air suspension module senses a compressor 2 overtemperature condition.

Action Taken When the DTC Sets
    • Air suspension functionality is suspended.
    • SERVICE AIR SUSPENSION message is displayed.

Conditions for Clearing the DTC

The DTC will clear when the condition for setting the DTC is removed.

Diagnostic Aids
    • This DTC is set when the compressor has run so long that it has overheated.
    • The compressor has overheated because of a blockage in the air system.
    • Bad compressor motor ground will set the DTC.

Test Description

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

  1. Tests whether the condition is module, system, or condition related.

    2.

  2. Tests for a short to voltage in the compressor battery positive voltage circuit or a defective air suspension relay.

    3.

  3. Tests if the DTC sets during normal operating conditions.

Step

Action

Yes

No

Schematic Reference: Air Suspension Schematics

1

Did you perform the Diagnostic System Check - Vehicle?

Go to Step 2

Go to Diagnostic System Check - Vehicle

2
  1. Install a scan tool.
  2. Turn ON the ignition, with the engine OFF.
  3. With a scan tool, monitor the DTC Information for DTC C0718 in the Air Suspension Module.

Does the scan tool indicate that DTC C0718 is current?

Go to Step 4

Go to Step 3

3

Most occurrences of this DTC are caused by overload of the compressor. Review the Air Suspension System with the customer to verify the conditions under which the DTC set.

Did vehicle operation cause this DTC to set?

Go to Diagnostic Aids

Go to Step 4

4

  1. Turn OFF the ignition.
  2. Check for a defective air suspension relay.
  3. Disconnect the air suspension relay. Test for a short to voltage in the compressor battery positive voltage circuit. Refer to Circuit Testing and Wiring Repairs.

Does the DTC reset?

Go to Step 5

System OK

5

Replace the air suspension compressor. Refer to Compressor Assembly Automatic Level Control Air Replacement .

Did you complete the replacement?

Go to Step 6

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6

  1. Use the scan tool in order to clear the DTCs.
  2. Operate the vehicle within normal operating conditions.

Does the DTC reset?

Go to Step 7

System OK

7
  1. Replace the air suspension module. Refer to Control Module References.
  2. Perform the trim height calibration procedure for the air suspension module if necessary after check trim height procedure.

Did you complete the replacement?

System OK

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