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:

    Heater Hose Coupling
    Special Tool(s) Remover, Heater Hose Inlet Tube 412-042 (T85T-18539-AH) Disconnect Tool, Heater Hose 412-127 Material Item Specification MERPOL - ESE-M99B144-B Disconnect CAUTION: Do not attempt to install a ...

    Rear Wheel Bearing and Axle Shaft Oil Seal
    Special Tool(s) Adapter for 303-224 205-153 (T80T-4000-W) Installer, Axle Shaft Bearing 205-124 (T78P-1225-A) Installer, Rear Axle Oil Seal 205-390 (T97T-1177-B) Remover, Axle Bearing 205-219 (T85L-1225-AH) S ...

    Heated windows and mirrors (if equipped)
    Heated Rear Window Note: The vehicle must be running to use this feature. Press the control to clear the rear window of thin ice and fog. Press the control again within 15 minutes to switch it off. It turns off automatically after approximately 15 minutes, or ...