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:

    Component Tests
    Engine Oil Leaks NOTE: When diagnosing engine oil leaks, the source and location of the leak must be positively identified prior to repair. Prior to carrying out this procedure, clean all sealing surface areas with a suitable solvent to remove all tra ...

    Fog Lamps
    Refer to Wiring Diagrams Cell 86 , Fog Lamps for schematic and connector information. Special Tool(s) 73 III Automotive Meter or equivalent 105-R0057 Principles of Operation The fog lamps will only illuminate when the low beam or parking l ...

    Disconnect
    1. Remove the A/C tube lock coupling clip (19E746), if equipped. 2. Fit the special tool to the spring lock coupling. 3. Push the tool into the cage opening to release the female fitting from the A/C tube lock coupling spring (19E576). 4. Pull the sprin ...