GM Service Manual Online
For 1990-2009 cars only

Object Number: 278745  Size: MF
ABS/TCS Schematics Front Mounted EBTCM/BPMV
ABS Components

Circuit Description

The IP monitors the master cylinder fluid level, if the fluid level becomes low the IP will turn on the Red BRAKE Warning indicator to inform the driver to have the hydraulic brake system checked.

Conditions for Setting the DTC

DTC C1248 can be set anytime ignition is present, and a low master cylinder fluid level has been detected by the IP and indicated to the EBTCM by the IP broadcasting a Class 2 message.

Action Taken When the DTC Sets

TCS/Active Handling are disabled.

    • Indicators that turn on:
       - RED Brake Warning indicator
       - Car Icon (TCS indicator)
    • Messages displayed on the DIC:
       - Service Traction System
       - Service Active HNDLG

Conditions for Clearing the DTC

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

Diagnostic Aids

    • If an intermittent malfunction exists refer to Testing for Electrical Intermittents in Wiring Systems.
    • DTC C1248 is used by the EBTCM for information only. It does not indicate a failure of the ABS/TCS/Active Handling system. For diagnosis of a low master cylinder fluid level condition refer to Brake Warning Indicator Always On in Hydraulic Brakes.