GM Service Manual Online
For 1990-2009 cars only

Circuit Description

The system relay supplies battery voltage to all six valve solenoids. The EBCM applies the ground(s) needed for solenoid activation. The low side of each solenoid coil has a feedback circuit to the EBCM. When the relay is commanded off, feedback voltage is low. When the relay is commanded on and the solenoid is commanded off, feedback voltage is high.

Conditions for Running the DTC

    • The ignition is ON.
    • The vehicle speed is greater than 6 km/h (4 mph).

Conditions for Setting the DTC

Open Solenoid DTC(s)

The EBCM detects low feedback voltage from a solenoid that is commanded off.

Shorted Solenoid DTC(s)

The EBCM detects high feedback voltage from a solenoid that is commanded on.

Action Taken When the DTC Sets

    • The ABS indicator is commanded on.
    • The ABS is disabled for the remainder of the ignition cycle.
    • The BRAKE indicator is commanded on and the DRP is disabled for the remainder of the ignition cycle (C0243, C0244, C0247 and C0248 only).

Conditions for Clearing the DTC

    • The condition(s) responsible for setting the DTC are no longer present.
    • A scan tool is used in order to clear the DTC.

Diagnostic Aids

An intermittent open/shorted solenoid DTC can be set by several different internal EBCM problems. Replace the EBCM if an open/shorted solenoid DTC continues to set intermittently.

Step

Action

Value(s)

Yes

No

1

Did you perform the ABS Diagnostic System Check?

--

Go to Step 2

Go to Diagnostic System Check

2

  1. Use a scan tool in order to clear the DTC(s).
  2. Use the scan tool in order to perform an ABS Function Test.

Does the DTC set?

--

Go to Step 3

Go to Diagnostic Aids

3

Important: Use the scan tool in order to perform the Tire Size Calibration procedure.

Replace the EBCM. Refer to Electronic Brake Control Module Replacement .

Did you complete the replacement?

--

Go to Step 4

--

4

  1. Use the scan tool in order to clear the DTC.
  2. Use the scan tool in order to perform an ABS Function Test.

Does the DTC set?

--

Go to Step 3

System OK