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For 1990-2009 cars only
Makes 🢒 Cadillac 🢒 2000 🢒 Eldorado 🢒 Brakes 🢒 Antilock Brake System 🢒 DTC C1255 EBCM Internal Malfunction

Circuit Description

This DTC identifies a malfunction within the electronic brake control module (EBCM).

Conditions for Running the DTC

The ABS conditions and the braking conditions are normal.

Conditions for Setting the DTC

An internal EBCM malfunction exists.

Action Taken When the DTC Sets

If equipped, the following actions occur:

    • The EBCM disables the ABS/TCS/VSES for the duration of the ignition cycle.
    • The ABS indicator turns ON.
    • The TRACTION CONTROL indicator turns ON.
    • The DIC displays the SERVICE STABILITY SYS message.
    • For some DTC C1255xx, the EBCM disables the variable effort steering (VES) for the duration of the ignition cycle and the DIC displays the SERVICE STEERING SYS message.

Conditions for Clearing the DTC
    • The condition for the DTC is no longer present (the DTC is not current) and you used the scan tool Clear DTC function.
    • The condition for the DTC is no longer present (the DTC is not current) and you used the On-Board Diagnostics Clear DTC function.
    • The EBCM automatically clears the history DTC when a current DTC is not detected in 50 consecutive drive cycles.

Diagnostic Aids
    • The scan tool displays 2 additional characters after the DTC. Take note of the 2 character code and any other DTCs that are set. The 2 character code is an engineering aid used in order to determine the cause of the internal malfunction.
    • A DTC C1255e2 can be caused by a battery or module disconnect. Inspect for a recent battery disconnect or module connector disconnect before replacing the EBCM.
    • A DTC C1255m5 can be set along with any wheel speed sensor DTC. Diagnose any wheel speed sensor DTCs before replacing the EBCM.
    • Make sure integrity of the connection between the EBCM and BPMV is secure, tight, and free from corrosion.

Test Description

The number below refers to the step number on the diagnostic table.

  1. This step determines whether the DTC is set current.

Step

Action

Value(s)

Yes

No

1

Did you perform the ABS Diagnostic System Check?

--

Go to Step 2

Go to Diagnostic System Check - ABS

2

  1. Install a scan tool.
  2. Turn ON the ignition, with the engine OFF.
  3. Use the scan tool in order to clear the DTCs.
  4. With the scan tool, perform the Automated Test.

Does the DTC reset?

--

Go to Step 3

Go to Step 4

3

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

Did you complete the repair?

--

Go to Step 4

--

4
  1. Use the scan tool in order to clear the DTCs.
  2. With the scan tool, perform the Automated Test.

Does the DTC reset?

--

Go to Step 2

System OK