Flow of Diagnosis

1. Verify the customer concern by operating the speed control to duplicate the condition.
2. Verify the speedometer operates properly without speed control by test driving the vehicle.
3. Verify the horn system operates by pressing the horn switch.
4. Visually inspect for obvious signs of mechanical and electrical damage.

VISUAL INSPECTION CHART

Mechanical
- Speed control actuator cable
- Throttle lever

Electrical
- Speed control actuator cable
- Throttle lever
- Blown fuse:
- Fuse junction panel Fuse 10 (10A)
- Loose or corroded connections
- Missing or bent terminals
- Circuitry open/shorted to ground
- Wire routing

5. If the concern remains after the inspection, connect NGS Tester. If NGS Tester does not communicate with the vehicle:
- Check that the program card is properly installed.
- Check the connections to the vehicle.
- Check the ignition switch position.
6. If NGS Tester still does not communicate with the vehicle, refer to the New Generation STAR Tester manual.
7. Perform the DATA LINK DIAGNOSTIC TEST. If NGS responds with:
- CKT914, CKT915 or CKT70 = ALL ECUS NO RESP/NOT EQUIP, diagnose Multiplex Communication Network concerns.
- NO RESP/NOT EQUIP for speed control servo, go to Pinpoint Test A. A: No Communication With The Module - Speed Control Servo
- SYSTEM PASSED, retrieve and record the continuous Diagnostic Trouble Codes (DTCs), erase the continuous DTCs and perform self-test diagnostics for the speed control servo.
8. If the DTCs retrieved are related to the concern, go to Speed Control Servo Diagnostic Trouble Code (DTC) Index to continue diagnostics. Speed Control Servo Diagnostic Trouble Code (DTC) Index
9. If no DTCs related to the concern are retrieved, proceed to the Symptom Chart to continue diagnostics. Symptom Related Diagnostic Procedures