GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 HUMMER 🢒 2004 🢒 H2 🢒 Suspension 🢒 Air Suspension 🢒 DTC B2795

Circuit Description

The air suspension module monitors the ride height switch signal circuit for a short to ground or battery with ignition on and up to 3 minutes with the ignition OFF.

Conditions for Running the DTC

Ignition ON or OFF.

Conditions for Setting the DTC

The air suspension module senses the ride height switch signal circuit voltage is shorted to ground or battery.

Action Taken When the DTC Sets
    • A DTC is set.
    • No 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 ride height switch circuitry is shorted to ground, voltage and open.

Test Description

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

  1. This step tests for normal scan tool data parameters.

    2.

  2. This step tests for data parameter change with scan tool.

    3.

  3. This step tests the signal circuit to be inactive.

Step

Action

Yes

No

Schematic Reference: Suspension Controls Schematics

1

Did you perform the Air Suspension Diagnostic System Check?

Go to Step 2

Go to Diagnostic System Check - Air Suspension

2

  1. Install a scan tool.
  2. Turn ON the ignition, with the engine OFF.
  3. With a scan tool, observe the ERH Switch parameter in the data list for the air suspension module.

Does the scan tool display released?

Go to Step 3

Go to Step 4

3

  1. Activate the ERH switch.
  2. With the scan tool, observe the ERH Switch parameter.

Does the ERH Switch parameter change state?

Go to Diagnostic Aids

Go to Step 4

4

  1. Turn OFF the ignition.
  2. Disconnect the ERH switch.
  3. Turn ON the ignition, with the engine OFF.
  4. With a scan tool, observe the ERH Switch parameter.

Does the scan tool display released?

Go to Step 7

Go to Step 5

5

Test the signal circuit of the ERH switch for a short to battery, ground or an open circuit. Refer to Circuit Testing and to Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 10

Go to Step 6

6

Inspect for poor connections at the harness connector of the air suspension module. Refer to Testing for Intermittent Conditions and Poor Connections and to Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 10

Go to Step 8

7

Inspect for poor connections at the harness connector of the ERH Switch. Refer to Testing for Intermittent Conditions and Poor Connections and to Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 10

Go to Step 9

8

Important: Always perform the check trim height procedure after air suspension module replacement.

  1. Replace the air suspension module. Refer to Module Assembly Electronic Suspension Control Replacement .
  2. Perform the trim height calibration procedure for the air suspension module if necessary after check trim height procedure.

Did you complete the replacement?

Go to Step 10

--

9

Replace the ride height switch. Refer to Rear Air Suspension Control Valve Switch Replacement .

Did you complete the replacement?

Go to Step 10

--

10
  1. Use the scan tool in order to clear the DTCs.
  2. Operate the vehicle within the Conditions for Running the DTC.

Does the DTC reset?

Go to Step 2

System OK