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:

    Engine Component View
    Cylinder Heads and Valve Train Components   Engine Front Cover Components   Engine Components   Cylinder Block and Lower End Components   Engine (DIAGNOSIS AND TESTING) Refer to Section for basic mechanical concerns or refer ...

    Dual-Function Pressure Switch (4.6L)
    The dual-function pressure switch is used to interrupt A/C compressor operation in the event of high system discharge pressures. The dual-function pressure switch is mounted on a Schrader valve-type fitting on the high pressure side of the A/C manifold ...

    911 Assistâ„¢
    WARNING: Unless the 911 Assist setting is set on prior to a crash, the system will not dial for help which could delay response time, potentially increasing the risk of serious injury or death after a crash. WARNING: Do not wait for 911 Assist to make an emerg ...