GM Service Manual Online
For 1990-2009 cars only

Circuit Description

The air suspension control module (ASCM) module provides power (a regulated 5 volts) to each of the position sensors. The ASCM module also monitors this voltage supply for a fault condition which prevents proper regulation.

DTC Descriptor

This diagnostic procedure supports the following DTC:

DTC C0696 Position Sensor Overcurrent (5 volt supply)

This vehicle has DTCs which include DTC Symptoms. For more information on DTC Symptoms, refer to DTC Symptom Description .

DTC Symptom

DTC Symptom Descriptor

00

No additional information

Conditions for Running the DTC

The ignition is ON.

Conditions for Setting the DTC

    • The position sensor supply voltage is outside the valid range of 4.855-5.25 volts.
    • The fault is detected for 1 second or more during ignition cycles, or during the same ignition cycle after clearing the DTC with a scan tool.

Action Taken When the DTC Sets

    • The ASCM module will set a current DTC
    • The SERVICE SUSPENSION SYS messages will be displayed.

Conditions for Clearing the MIL/DTC

    • The scan tool can be used to clear the DTC.
    • The DTC is saved as history when the ASCM module no longer sees a position sensor supply voltage outside the valid range of 4.855-5.25 volts. The DTC will clear if the fault does not return after 50 consecutive ignition cycles.

Diagnostic Aids

Refer to Testing for Intermittent Conditions and Poor Connections .

Test Description

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

  1. This step determines if the fault is due to a short to ground.

  2. This step determines if the fault is due to a short to voltage.

  3. This step tests for a short to ground in the position sensor supply circuits.

  4. This step tests for a short between the position sensor supply and ground circuits.

  5. This step tests for a short to voltage in the position sensor supply circuits.

Step

Action

Value(s)

Yes

No

Schematic Reference: Suspension Controls 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, with the engine OFF.
  2. Measure the voltage from the 5-volt reference circuit of the electronic suspension control (ASCM) module to the left rear position sensor by backprobing the ASCM module connector.

Does the voltage measure less than the specified value?

4.85 V

Go to Step 4

Go to Step 3

3

Does the voltage measure greater than the specified value?

5.25 V

Go to Step 6

Go to Step 7

4

Test the 5-volt reference circuit of each position sensor for a short to ground. Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

--

Go to Step 8

Go to Step 5

5

Test for a short between the 5-volt reference circuit and the ground circuit of each position sensor. Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

--

Go to Step 8

Go to Step 7

6

Test the 5-volt reference circuit of each position sensor for a short to voltage. Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

--

Go to Step 8

Go to Step 7

7

Replace the air suspension control module. Refer to Air Suspension Control Module Replacement .

Did you complete the replacement?

--

Go to Step 8

--

8

  1. Use the scan tool in order to clear the DTCs .
  2. 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