Passive Entry System

WARNING: This page is about a different car, the 2011 Jeep Grand Cherokee. However, it is still accessible from the selected car via links, so may be relevant.

In the Passive Entry (PE) system the doors and the liftgate are unlocked passively; however, they must still be locked actively after exiting the vehicle using the tactile Lock button on either front door handle or the liftgate handle and light bar unit. When the system senses a hand approaching the capacitive switch in the door handle grip or detects a button press of the liftgate Lock and Unlock switch, it sends out challenge messages through the Low Frequency (LF) antennas to authenticate the presence and location of a valid FOB with Integrated Key (FOBIK).

The FOBIK responds by sending a Very High Frequency (VHF) message back to the receiver within the Passive Entry Module (PEM). If the PEM determines the FOBIK is valid and that it is located outside the vehicle in the same zone or vicinity as the door handle or liftgate switch being activated, it sends an electronic Unlock Request message over the Controller Area Network (CAN) data bus to the TIPM to automatically unlock and allow entry to that door.

The PE system circuits and FOBIK inputs are continually monitored by the microprocessor and software contained within the PEM. When the PEM monitors a problem in any of the PE system circuits or FOBIK inputs, it stores a DTC in its memory circuit. The hard wired circuits between components related to the PE 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 PE system or the electronic controls or communication between other modules and devices that provide features of the PE system. The most reliable, efficient, and accurate means to diagnose the PE system or the electronic controls and communication related to PE 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.