Initial Inspection and Diagnostic Overview

1. Verify the customer concern by operating the Vehicle Emergency Message System (VEMS). Observe the information and message center display while operating the VEMS. If there is no status information displayed by the information and message center display, refer to Instrument Panel, Gauges and Warning Indicators.

NOTE: The Remote Emergency Satellite Cellular Unit (RESCU) module must be reconfigured upon replacement.

2. Visually inspect for obvious signs of electrical damage.

VISUAL INSPECTION CHART

Electrical
^ Battery Junction Box (BJB) Fuse 414 (5 A)
^ Central Junction Box (CJB) Fuse 229 (5 A)
^ Cellular phone system
^ Circuitry
^ Console RESCU switch
^ RESCU module
^ Global Positioning Sensor (GPS) antenna coaxial cable and connectors
^ Portable Support Electronics (PSE) module

3. Verify the cellular phone system has an activated service.
4. If the concern remains after the inspection, connect the diagnostic tool to the Data Link Connector (DLC) located beneath the instrument panel and select the vehicle to be tested from diagnostic tool menu. If diagnostic tool does not communicate with the vehicle:
^ check that the program card is correctly installed.
^ check the connections to the vehicle.
^ check the ignition switch position.
5. If the Diagnostic Tool still does not communicate with the vehicle, refer to the diagnostic tool manual.
6. Carry out the DATA LINK DIAGNOSTICS. If the diagnostic tool responds with:
^ CKT914, CKT915 or CKT70 = ALL ECUS NO RESP/NOT EQUIP, refer to Module Communications Network (Information Bus).
^ NO RESP/NOT EQUIP for RESCU, go to Pinpoint Test A. Test A: No Communication With The RESCU
^ SYSTEM PASSED, retrieve and record the continuous Diagnostic Trouble Codes (DTCs), clear the continuous DTCs and carry out self-test diagnostics for the RESCU module.
7. If the DTCs retrieved are related to the concern, go to RESCU Diagnostic Trouble Code (DTC) Index. Diagnostic Trouble Code Tests and Associated Procedures
8. If no DTCs related to the concern are retrieved, proceed to the Symptom Chart. Symptom Related Diagnostic Procedures