Inspection and Verification
NOTE:^ If any concerns are noted with the speedometer or horn, address those concerns by referring to their associated systems before continuing speed control diagnosis.
^ When in speed control mode, initial depression of the clutch pedal may cause a normal momentary increase of engine rpm.
^ If the vehicle is a diesel, refer to Powertrain Management.
1. Verify the customer concern by operating the speed control system.
2. Visually inspect for obvious signs of mechanical and electrical damage.
Visual Inspection Chart:
Visual Inspection Chart
3. If the fault is not visually evident, go to the Self-Test Diagnostics - Excursion or Super Duty (Excursion, Super Duty), or verify the symptom and proceed to the Symptom Chart (Motorhome). Reading and Clearing Diagnostic Trouble Codes Diagnosis By Symptom