GM Service Manual Online
For 1990-2009 cars only

Circuit Description

The system relays are energized when the ignition is ON and the vehicle speed is greater than 6 km/h (4 mph). The system relay supplies voltage to the solenoid valves and to the pump motor. This voltage is referred to as the system voltage. The EBCM controls the solenoid valves by grounding the control circuit.

DTC Descriptors

This diagnostic procedure supports the following DTCs:

    • DTC C0241 EBCM Control Valve Circuit
    • DTC C0242 EBCM Control Valve Circuit
    • DTC C0243 EBCM Control Valve Circuit
    • DTC C0244 EBCM Control Valve Circuit
    • DTC C0245 EBCM Control Valve Circuit
    • DTC C0246 EBCM Control Valve Circuit
    • DTC C0247 EBCM Control Valve Circuit
    • DTC C0248 EBCM Control Valve Circuit

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

The EBCM detects an internal malfunction.

Action Taken When the DTC Sets

C0241, C0242, C0245, C0246, C0251, C0252, C0253, C0254

If equipped, the following actions occur:

    • The EBCM disables the DRP/ABS.
    • The ABS indicator turns ON.
    • The red Brake warning indicator turns ON.
    • The DIC displays the SERVICE BRAKE SYSTEM message.

C0243, C0244, C0247, C0248

If equipped, the following actions occur:

    • The EBCM disables the ABS.
    • The ABS indicator turns ON.
    • The DIC displays the SERVICE BRAKE SYSTEM message.

Conditions for Clearing the DTC

The conditions for setting the DTC are no longer present and you use the scan tool Clear DTCs function.

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

Yes

No

1

Did you perform the Diagnostic System Check - Vehicle?

Go to Step 2

Go to Diagnostic System Check - Vehicle

2

  1. Use a 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 set?

Go to Step 3

Go to Diagnostic Aids

3

Replace the electronic brake control module (EBCM). Refer to Control Module References for replacement, setup, and programming.

Did you complete the replacement?

Go to Step 4

--

4

  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 3

System OK