Power Locks: Testing and Inspection

DIAGNOSIS AND TESTING - POWER LOCKS
These tests will help to diagnose the hard wired components and circuits of the power lock system. However, these tests may not prove conclusive in the diagnosis of this system. In order to obtain conclusive testing of the power lock and RKE systems, the Programmable Communication Interface (PCI) data bus network and all of the electronic modules that provide inputs to, or receive outputs from the power lock and RKE system components must be checked.

The most reliable, efficient, and accurate means to diagnose the power lock and RKE systems requires the use of a DRBIII scan tool. The DRBIII scan tool can provide confirmation that the PCI data bus is functional, that all of the electronic modules are sending and receiving the proper messages on the PCI data bus, that the Central Timer Module (CTM) is receiving the proper hard wired inputs, and that the power lock motors are being sent the proper hard wired outputs by the CTM.

PRELIMINARY TESTS
To begin this test, note the system operation while you actuate both the Lock and Unlock functions with the power lock switches, the door cylinder lock switches (if equipped with the optional Vehicle Theft Security System (VTSS), and the RKE transmitter. Then, proceed as follows:
- If the entire power lock system fails to function with the power lock switches, the door cylinder lock switches, or the RKE transmitter, check the fused B(+) fuse in the Junction Block (JB). If the fuse is OK, proceed to the diagnosis of the power lock motors.
- If the power lock system functions with both power lock switches, and both the door cylinder lock switches, but not with the RKE transmitter, proceed to the diagnosis of the transmitter. (Refer to REMOTE KEYLESS ENTRY TRANSMITTER - DIAGNOSIS AND TESTING).
- If the entire power lock system functions with the RKE transmitter, and both door cylinder lock switches, but not with one or both of the power lock switches, proceed to diagnosis of the Driver Door Module (DDM) for the driver side switch or to power lock switch for the passenger side switch. (Refer to DRIVER DOOR MODULE - DIAGNOSIS AND TESTING) and/or (POWER LOCK SWITCH - DIAGNOSIS AND TESTING)
- If the entire power lock system functions with the RKE transmitter, and both power lock switches, but not with one or all of the door cylinder lock switches, proceed to diagnosis of the door cylinder lock switches. (Refer to DOOR CYLINDER LOCK SWITCH - DIAGNOSIS AND TESTING).
- If one power lock motor fails to operate with both of the power lock switches, all of the door cylinder lock switches, and/or the RKE transmitter, proceed to diagnosis of the power lock motor. (Refer to POWER LOCK MOTOR - DIAGNOSIS AND TESTING).

If the problem being diagnosed is related to one or more of the electronic features (automatic locks, driver door unlock only, door lock inhibit, enhanced accident response, illuminated entry, panic mode, RKE horn chirp, or RKE optical chirp), further diagnosis should be performed using a DRBIII scan tool. Refer to the appropriate diagnostic information.