GM Service Manual Online
For 1990-2009 cars only

Important: Review the system operation in order to familiarize yourself with the system functions. Refer to the following:

   •  Brake Warning System Description and Operation
   •  Hydraulic Brake System Description and Operation
   •  Brake Booster Pump Description and Operation
Perform the Brake System Vehicle Road Test before using the brake symptoms tables in order to duplicate the customer's concern.

Visual/Physical Inspection

  1. Inspect for aftermarket devices which may affect the operation of the instrument panel cluster. Refer to Checking Aftermarket Accessories .
  2. Inspect for aftermarket devices which may affect the operation of the hydraulic brake system.
  3. Inspect the easily accessible or visible system components for obvious damage or conditions which may cause the symptom.

Intermittents

Faulty electrical connections or wiring may be the cause of intermittent conditions. Refer to Testing for Continuity .

Symptom List

Refer to a symptom diagnostic procedure from the following list in order to diagnose the symptom:

    •  Brake Warning Indicator Always On
    •  Brake Warning Indicator Inoperative
    •  Brakes Drag