GM Service Manual Online
For 1990-2009 cars only

All diagnostics on a vehicle should follow a logical process. Strategy Based Diagnostics is a uniform approach for repairing all systems. The diagnostic flow is the place to start when repairs are necessary and may always be used in order to resolve a system problem. For a detailed explanation, refer to Strategy Based Diagnosis .

Visual/Physical Inspection

    • Inspect for aftermarket or non-OEM devices such as, but not including; tailpipe extensions, headers, and exhaust cutouts. This could affect the operation and proper performance of the exhaust brake system.
    • Verify the exact operating conditions under which the concern exists. Note factors such as engine RPM, engine temperature, engine load, vehicle speed, and frequency of concern.
    • Inspect the easily accessible or visible system components for obvious damage or conditions which could cause any symptom.

Intermittent

Test the vehicle under the same conditions that the customer reported in order to verify the system is operating as designed.

Symptom List

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

    • Loss of Power
        Refer to Exhaust Brake Always On .
    • Poor acceleration
        Refer to Exhaust Brake Always On .
    • Excessive smoke, diesel
        Refer to Exhaust Brake Always On .
    • Exhaust hissing noise
        Refer to Exhaust Brake Always On .
    • Exhaust brake inoperative
        Refer to Exhaust Brake Inoperative .
    • Exhaust brake always on
        Refer to Exhaust Brake Always On .
    • Exhaust brake indicator is inoperative
        Refer to Exhaust Brake Indicator Lamp Inoperative .