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:

    Lamp Switch - Headlamp
    Removal 1. Disconnect the battery ground cable. 2. Remove the headlamp switch knob. 1. Pull the headlamp switch knob out. 2. Insert a thin tool into the slot, pull and remove the headlamp switch knob. 3. Remove the instrument panel cluster fin ...

    Rear Bumper
    Removal and Installation All vehicles 1. Remove the rear bumper cover. For additional information, refer to Rear Bumper Cover in this section. 2. Remove the rear bumper cover isolator. Vehicles with 4.6L engines 3. Remove the bolts and the exhaust outlet pip ...

    Valve Spring Strength
    Special Tool(s) Pressure Gauge, Valve/Clutch Spring 303-006 (TOOL-6513-DD) or equivalent 1. Use a Valve/Clutch Spring Pressure Gauge to check the valve spring for correct strength at the specified valve spring length. Refer to the appr ...