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:

  1. Perform the Brake System Vehicle Road Test before using the brake symptom tables in order to duplicate the customer's concern.
  2. Review the system description and operation in order to familiarize yourself with the system functions. Refer to the following:
  3.    •  Hydraulic Brake System Description and Operation
       •  Brake Warning System Description and Operation
       •  Brake Assist System Description and Operation
       •  Disc Brake System Description and Operation in Disc Brakes
       •  Drum Brake System Description and Operation in Drum Brakes
       •  Park Brake System Description and Operation in Park Brake
       •  ABS Description and Operation in Antilock Brake System

Visual/Physical Inspection

  1. Inspect for aftermarket devices which may affect the operation of the instrument panel cluster. Refer to Checking Aftermarket Accessories in Wiring Systems.
  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.

Intermittent

Faulty electrical connections or wiring may be the cause of intermittent conditions. Refer to Testing for Intermittent Conditions and Poor Connections in Wiring Systems.

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
    •  Brake Pulsation
    •  Brake System Noise
    •  Braking Action Uneven - Pulls to One Side
    •  Braking Action Uneven - Front to Rear
    •  Brake Pedal Excessive Travel
    •  Brake Pedal Excessive Effort
    •  Brakes Drag
    •  Brake System Slow Release
    •  Brake Fluid Loss
    •  Park Brake Will Not Hold or Release in Park Brake