Component Tests and General Diagnostics

1. Check RADIO Fuse for an open. If the Fuse is blown check CKT 640 for a short to ground.
2. Check that G200 is clean and tight.
3. Always check terminal contact before replacing any component.
4. If the Remote Driver's Door Unlock Control Modes are not functioning properly, set the mode the customer wants and test its function. If it is inoperative refer to the Symptom Table for appropriate diagnostic procedure.
5. If the Remote Lock and Unlock Confirmation Modes are not functioning properly, set the mode the customer wants and test its function. If it is inoperative refer to the Symptom Table for appropriate diagnostic procedure.
6. Be certain to verify proper Power Door Lock function before beginning Keyless Entry diagnosis. Refer to Automatic Door Locks. Power Locks
7. Be certain to verify proper Rear Compartment Lid Release function before beginning Keyless Entry diagnosis. Refer to Rear Compartment Lid Release. Trunk / Liftgate
8. If door locks operate from the Transmitter, but not from the Door Lock Switches, check continuity of Door Lock Switch and associated wiring for an open or a short. Repair/replace as necessary.
9. Check Transmitter Battery terminals. They should be clean and make good contact with the Battery.
10. If in doubt as to the condition of the Transmitter batteries, replace them with new ones. Measuring battery voltage with a DMM may show a weak Battery as being good.
11. If a second Transmitter is available, try it. If it works, remove the batteries and install them in the first Transmitter. If the first Transmitter still doesn't work, resynchronize the Transmitter. If the first Transmitter still does not work, reprogram the transmitter, and if it is still inoperative, replace the Transmitter.
12. Each Door Lock Actuator contains an electronic circuit breaker. The resistance in the Door Lock Actuator increases if the Actuator is overloaded, and the resistance will return to normal after voltage is removed from the Actuator terminals.
^ 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 (refer to General Troubleshooting Procedures). Diagnostic Aids
^ Refer to System Diagnosis.