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:

    Manual seats
    WARNING: Do not adjust the driver’s seat or seatback while the vehicle is moving. WARNING: Rock the seat backwards and forwards after releasing the lever to make sure that it is fully engaged. Moving the seats backward and forward Recline adjustment WARNIN ...

    Wheel Studs
    Special Tool(s) C-Frame and Clamp Assembly 211-023 (T74P-3044-A1) Removal CAUTION: Suspension fasteners are critical parts because they affect performance of vital components and systems and their failure can result in major service expense. A ...

    Component Tests
    Grid Wire Test 1. Using a bright lamp inside the vehicle, inspect the wire grid from the exterior. A broken grid wire will appear as a brown spot. 2. Run the engine at idle. Set the rear window defrost switch to ON. The indicator light should co ...