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:

    Piston - Ring-to-Groove Clearance
    1. Inspect the piston for ring land damage or accelerated wear. 2. Measure the piston ring-to-groove clearance. Refer to the appropriate section in Group for the procedure. If out of specification, install new components as necessary. Refer to the a ...

    Brake Caliper Support Bracket
    Removal 1. Raise and support the vehicle. 2. Remove the tire and wheel assembly. 3. CAUTION: Do not allow the rear disc brake caliper (2552) to hang from the rear wheel brake hose (2A442) Remove the rear disc brake caliper bolts and position the ...

    Fuel quality
    Note: Use of any fuel other than those recommended may cause powertrain damage and a loss of vehicle performance; repairs may not be covered under warranty. Choosing the Right Fuel Use only unleaded fuel or unleaded fuel blended with a maximum of 15% ethanol. ...