GM Service Manual Online
For 1990-2009 cars only

Object Number: 490157  Size: MF

Circuit Description

This DTC identifies a malfunction within the EBCM.

Conditions for Running the DTC

The ABS/TCS conditions are normal.

Conditions for Setting the DTC

DTC C1255 is set when an internal EBCM malfunction exists.

Action Taken When the DTC Sets

If equipped, the following actions occur:

    • The EBCM disables the ABS/TCS for the duration of the ignition cycle.
    • The EBCM temporarily suspends the TIM monitoring function while the DTC is set.
    • The ABS indicator turns ON.
    • The Traction Off indicator turns ON.
    • The message center displays the Service Traction System and the Low Tire Pressure message.

Conditions for Clearing the DTC

    • Condition for DTC is no longer present and scan tool clear DTC function is used.
    • 100 ignition cycles have passed with no DTCs detected.

Diagnostic Aids

    • When DTC C1255 is displayed on the Scan Tool, it will be followed by two more numbers which should be noted along with any other DTCs that may be displayed. The additional two numbers displayed with DTC C1255 are for aiding engineering to determine the cause of the internal malfunction.
    • Make sure the integrity of the connection between the EBCM and the BPMV is clean, secure, tight, and free from corrosion.

Step

Action

Value(s)

Yes

No

1

Did you perform the ABS Diagnostic System Check?

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Go to Step 2

Go to Diagnostic System Check - ABS

2

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

Did you find and correct the condition?

--

Go to Diagnostic System Check - ABS

Go to Step 3

3

Replace the EBCM. Refer to Electronic Brake Control Module Replacement

Did you complete the repair?

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Go to Diagnostic System Check - ABS

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