Diagnosis And Testing - Sentry Key Immobilizer System

WARNING: This page is about a different car, the 2017 Jeep Cherokee. However, it is still accessible from the selected car via links, so may be relevant.

WARNING:

To avoid serious or fatal injury on vehicles equipped with airbags, disable the Supplemental Restraint System (SRS) before attempting any steering wheel, steering column, airbag, Occupant Classification System (OCS), seat belt tensioner, impact sensor or instrument panel component diagnosis or service. Disconnect and isolate the battery negative (ground) cable, then wait two minutes for the system capacitor to discharge before performing further diagnosis or service. This is the only sure way to disable the SRS. Failure to follow these instructions may result in accidental airbag deployment.

The hard-wired circuits between modules and components related to the Sentry Key Immobilizer System (SKIS) may be diagnosed using conventional diagnostic tools and procedures. Refer to the appropriate wiring information. The wiring information includes wiring diagrams, 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 SKIS or the electronic controls and communication between other modules and devices that provide features of the SKIS. The most reliable, efficient and accurate means to diagnose the SKIS or the electronic controls and communication related to SKIS operation requires the use of a diagnostic scan tool. Refer to the appropriate diagnostic information.

SENTRY KEY IMMOBILIZER SYSTEM DIAGNOSIS
CONDITION	POSSIBLE CAUSES	CORRECTION
SECURITY INDICATOR FAILS TO LIGHT DURING BULB TEST	1. Ineffective Light-Emitting Diode (LED).	1. Use a diagnostic scan tool to perform the Instrument Panel Cluster (IPC) actuator test. Refer to the appropriate diagnostic information.
	2. Ineffective security indicator circuit.	2. Check the security indicator circuit between the Body Control Module (BCM) and the IPC for an open or short. Repair the circuit, if required.
	3. Ineffective ground circuit.	3. Test and repair the open ground circuit at the connector for the IPC, if required.
	4. Ineffective battery feed circuit.	4. Test and repair the open battery feed circuit at the connector for the IPC, if required.
	5. Ineffective ignition feed circuit.	5. Test and repair the open ignition feed circuit at the connector for the IPC, if required.
SECURITY INDICATOR FLASHES FOLLOWING BULB TEST	1. Invalid key or Frequency Operated Button with Integrated Key (FOBIK) in the ignition.	1. Remove the invalid key or FOBIK and try again with a known valid key or FOBIK.
SECURITY INDICATOR FLASHES FOLLOWING BULB TEST	2. Key-related fault.	2. Use a diagnostic scan tool and the appropriate diagnostic information for further diagnosis.
SECURITY INDICATOR LIGHTS SOLID FOLLOWING BULB TEST	1. SKIS system malfunction/fault detected.	1. Use a diagnostic scan tool and the appropriate diagnostic information for further diagnosis.
SECURITY INDICATOR LIGHTS SOLID FOLLOWING BULB TEST	2. SKIS system ineffective.	2. Use a diagnostic scan tool and the appropriate diagnostic information for further diagnosis.