Ford Mustang (1999-2004) Service Manual: Inspection and Verification

NOTE: If any concerns are noted with the speedometer, stoplamps, or horn, address those concerns by referring to their associated sections before continuing speed control diagnosis.

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

Mechanical Electrical
  • Deactivator switch
  • Speed control actuator cable not attached to throttle
  • Speed control actuator cable not fully seated to the engine bracket
  • Central junction box (CJB) Fuse:
  • 15 (15A)
  • 33 (15A)
  • 35 (15A)
  •  Battery junction box (BJB) fuse:
  • HORN (20A)
  • Wiring harness
  • Loose or corroded connections
  • Speed control actuator switches

3. If the fault is not visually evident, verify the symptom and GO to the Symptom chart.

    Principles of Operation
    The speed control system is designed to maintain vehicle speed above 48 km/h (30 mph). After the ON switch is depressed, depressing the SET/ACCEL switch will activate the speed control servo. To inc ...

    Symptom Chart
    NOTE: New speed control diagnostic software is available in Version 12 or higher for the diagnostic tool. When using this software, it is necessary to use Next Generation Speed Control Adapter 007- ...

    Other materials:

    Symptom Chart
    Condition Possible Sources Action Hard Steering or Lack of Assist Seized lower steering column shaft U-joints. Damaged, fractured steering column bearing(s). Power steering pump. Suspension components. ...

    System Air Flow Description
    MAX A/C When MAX A/C is selected: The air inlet door vacuum control motor is at full vacuum, closing off outside air and admitting only recirculated air. The panel/defrost door vacuum control motor is at full vacuum and the panel/floor door vacu ...

    Vehicle identification number
    The vehicle identification number is located on the driver’s side instrument panel. Please note that in the graphic, XXXX is representative of your vehicle identification number. The Vehicle Identification Number (VIN) contains the following information: ...