Power Locks - Operation

OPERATION

POWER LOCK SYSTEM

The power lock system uses non-switched battery current received through a fused B(+) fuse so that the system remains operational regardless of the ignition switch position. The Body Control Module (BCM) is the primary power lock system controller. The power lock switch (also known as the door inhibit switch) is hard wired to the BCM.

When the BCM receives an input from the power lock switch, it provides the appropriate hard wired control outputs to energize or de-energize the power lock relays soldered onto its printed circuit board. The relays control the flow of battery current and ground to each of the power lock motors to lock or unlock each of the door and liftgate latches. The BCM also monitors hard wired inputs from the liftgate latch release switch. The BCM uses all of these inputs and internal programming to determine whether or not to provide the output necessary to operate the liftgate latch release solenoid.

The BCM also stores the power lock system Customer Programmable feature settings received from the Electronic Vehicle Information Center (EVIC) circuitry of the Instrument Panel Cluster (IPC). The BCM uses these settings and internal programming along with hard wired and electronic message inputs to determine the proper outputs needed to produce each of the appropriate power lock system features.

The power lock system circuits are continually monitored and controlled by the microprocessor and software contained within the BCM. When the BCM monitors a problem in any of the power lock system circuits or components, it stores a fault code or Diagnostic Trouble Code (DTC) in its memory circuit. The hard wired circuits between components related to the power lock system may be diagnosed using conventional diagnostic tools and procedures. Refer to the appropriate wiring information. The wiring information includes wiring diagrams, proper wire and connector repair procedures, details of wire harness routing and retention, connector pin-out information and location views for the various wire harness connectors, splices and grounds.

However, conventional diagnostic methods will not prove conclusive in the diagnosis of the power lock system or the electronic controls or communication between other modules and devices that provide some features of the power lock system. The most reliable, efficient, and accurate means to diagnose the power lock system or the electronic controls and communication related to power lock system operation, as well as the retrieval or erasure of a DTC requires the use of a diagnostic scan tool. Refer to the appropriate diagnostic information.

REMOTE KEYLESS ENTRY SYSTEM

The Remote Keyless Entry (RKE) system uses non-switched battery current received through a fused B(+) fuse so that the system remains operational regardless of the ignition switch position. The Body Control Module (BCM) is the primary RKE system controller as well as the Radio Frequency (RF) RKE receiver. The BCM validates the vehicle access code of each RKE transmitter from which it receives RF signal inputs. It ignores requests from any transmitter for which it has no stored vehicle access code. When the BCM receives an input from a valid transmitter source, it uses internal programming to provide the appropriate hard wired outputs to invoke the proper RKE system features and responses.

The RKE system circuits and transmitter inputs are continually monitored by the microprocessor and software contained within the BCM. When the BCM monitors a problem in any of the RKE system circuits or transmitters, it stores a DTC in its memory circuit. The hard wired circuits between components related to the RKE system may be diagnosed using conventional diagnostic tools and procedures. Refer to the appropriate wiring information. The wiring information includes wiring diagrams, proper wire and connector repair procedures, details of wire harness routing and retention, connector pin-out information and location views for the various wire harness connectors, splices and grounds.

However, conventional diagnostic methods will not prove conclusive in the diagnosis of the RKE system or the electronic controls and devices that provide features of the RKE system. The most reliable, efficient, and accurate means to diagnose the RKE system or the electronic controls related to RKE system operation, as well as the retrieval or erasure of a DTC requires the use of a diagnostic scan tool. Refer to the appropriate diagnostic information.