Inspection and Verification

1. Verify the customer concern by operating the speed control to duplicate the condition.
2. Verify the speedometer operates correctly without speed control by test driving the vehicle. If the speedometer does not operate correctly, refer to Instrument Panel, Gauges and Warning Indicators.
3. Verify the horn system operates by pressing the horn switch. If the horn system does not operate, refer to Horn.

Visual Inspection Chart:

4. Visually inspect for obvious signs of mechanical and electrical damage.
5. If the concern remains after the inspection, connect the diagnostic tool. 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.
6. If the diagnostic tool still does not communicate with the vehicle, refer to the diagnostic tool manual.
7. Carry out the DATA LINK DIAGNOSTIC TEST. If the diagnostic tool responds with:
^ SCP+, SCP- or ISO = ALL ECUS NO RESP/NOT EQUIP, refer to Module Communications Network (Information Bus).
^ NO RESP/NOT EQUIP for speed control servo, go to Pinpoint Test A. [1][2]Pinpoint Tests
^ SYSTEM PASSED, retrieve and record the continuous Diagnostic Trouble Codes (DTCs), erase the continuous DTCs and carry out self-test diagnostics for the speed control servo. Diagnostic Trouble Code Tests and Associated Procedures
8. If the DTCs retrieved are related to the concern, go to Speed Control Servo Diagnostic Trouble Code (DTC) Index to continue diagnostics. Diagnostic Trouble Code Tests and Associated Procedures
9. If no DTCs related to the concern are retrieved, proceed to the Symptom Chart to continue diagnostics. Diagnosis By Symptom