Troubleshooting Hints

PERFORM BEFORE BEGINNING SYSTEM DIAGNOSIS
1 Check that G400 is clean and tight.
2. Check PWR ACCY Fuse 7 and Courtesy Fuse 8 for open. If either fuse is open, check for short to ground through CKTs 640 and/or 40.
3. For vehicles with Manual Transmissions, the "BRAKE" Indicator receives a ground through the Park Brake Switch. Applying the Park Brake and observing the "BRAKE" Indicator can be used as a quick check of the ground CKT below S228.
^ Check for a broken (or partially broken) wire inside of the insulation which could cause system malfunction but prove "GOOD" in a continuity/voltage check with a system disconnected. These circuits may be intermittent or resistive when loaded, and if possible, should be checked by monitoring for a voltage drop with the system operational (under load).
^ Check for proper installation of aftermarket electronic equipment which may affect the integrity of other systems (see "Troubleshooting Procedures"). Diagnostic Aids
^ Refer to System Diagnosis.