GM Service Manual Online
For 1990-2009 cars only

Circuit Description

The instrument panel cluster (IPC) supplies 12 volts to the supplemental brake assist (SBA) module via the supplemental brake assist signal circuit. The SBA toggles this voltage to ground to produce a valid supplemental brake assist signal.

Conditions for Running the DTC

The ignition is ON.

Conditions for Setting the DTC

    • The IPC does not receive a valid health signal from the SBA for 5 consecutive ignition cycles.
    • The SBA is producing a supplemental brake assist signal indicating a system failure.

Action Taken When the DTC Sets

The service brake booster message is displayed.

Conditions for Clearing the DTC

The scan tool is used to clear the DTC.

Step

Action

Yes

No

1

Did you perform the Driver Information Systems Diagnostic System Check?

Go to Service Brake Booster Message Displayed

Go to Diagnostic System Check - Driver Information Systems in Instrument Panel, Gages, and Console