Initial Inspection and Diagnostic Overview

INSPECTION AND VERIFICATION

1. Verify the customer concern by operating the horn system.

Visual Inspection Chart:

2. Visually inspect for obvious signs of mechanical and electrical damage.
3. 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 the diagnostic tool menu. If the 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.

4. If the diagnostic tool still does not communicate with the vehicle, refer to the diagnostic tool manual.
5. Carry out the DATA LINK DIAGNOSTICS TEST. If the diagnostic tool responds with:
- CKT914, CKT915, CKT693 or CKT70 = ALL ECUS NO RESP/NOT EQUIP, refer to Module Communications Network (Information Bus).
- NO RESP/NOT EQUIP for vehicle security module, refer to Multifunction Electronic Control Module (General Module).
- SYSTEM PASSED, retrieve and record the continuous diagnostic trouble codes (DTCS), erase the continuous DTCs and carry out self-test diagnostics for the vehicle security module.

6. If the DTCs retrieved are related to the concern, go to the vehicle security module (DTC) Index to continue diagnostics. Diagnostic Trouble Code Tests and Associated Procedures
7. If no DTCs related to the concern are retrieved, proceed to the Symptom Chart to continue diagnostics. Symptom Related Diagnostic Procedures