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For 1990-2009 cars only

DTC C0241-C0254 or C041-C054 EBCM Control Valve Circuit 310 ABS

Circuit Description

The EBCM internal relay supplies battery voltage to all six valve solenoids. The EBCM applies the grounds needed to activate each solenoid. The low side of each solenoid coil has a feedback circuit to the EBCM microprocessor. When a solenoid is commanded off, feedback voltage is high. When a solenoid is commanded on, feedback voltage is low.

Conditions for Running the DTC

    • The ignition is ON.
    • The IPC bulb check is complete.
    • The vehicle is moving at a speed greater than 5 km/h (3 mph).

Conditions for Setting the DTC

Open Solenoid/Shorted Control Circuit DTC(s)

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

Shorted Solenoid/Open Control Circuit DTC(s)

The EBCM microprocessor 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 (C0243, C0244, C0247 and C0248 only).

Conditions for Clearing the DTC

    • Repair the condition(s) responsible for setting the DTC.
    • Use a scan tool in order to clear the DTC.

Diagnostic Aids

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

Step

Action

Value(s)

Yes

No

Schematic Reference: Antilock Brake System Schematics

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

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

Did you find and correct the condition?

--

Go to Step 5

Go to Step 4

4

Important: Perform the Tire Size Calibration procedure.

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

Did you complete the replacement?

--

Go to Step 5

--

5

  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

DTC C0241-C0254 or C041-C054 EBCM Control Valve Circuit 325 ABS

Circuit Description

The EBCM internal relay supplies battery voltage to all six valve solenoids. The EBCM applies the grounds needed to activate each solenoid. The low side of each solenoid coil has a feedback circuit to the EBCM microprocessor. When a solenoid is commanded off, feedback voltage is high. When a solenoid is commanded on, feedback voltage is low.

Conditions for Running the DTC

    • The ignition is ON.
    • The IPC bulb check is complete.
    • The vehicle is moving at a speed greater than 5 km/h (3 mph).

Conditions for Setting the DTC

Open Solenoid/Shorted Control Circuit DTC(s)

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

Shorted Solenoid/Open Control Circuit DTC(s)

The EBCM microprocessor 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

    • Repair the condition(s) responsible for setting the DTC.
    • Use a scan tool in order to clear the DTC.

Diagnostic Aids

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

Step

Action

Value(s)

Yes

No

Schematic Reference: Antilock Brake System Schematics

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

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

Did you find and correct the condition?

--

Go to Step 5

Go to Step 4

4

Important: Perform the Tire Size Calibration procedure.

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

Did you complete the replacement?

--

Go to Step 5

--

5

  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