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:

    Pinpoint Test D: LFC 15/DTC B 1887- Driver Air Bag Circuit Shorted to Ground
    Normal Operation The restraints control module (RCM) checks for driver air bag circuit shorts to ground by monitoring the voltage of circuits 614 (GY/OG) and 615 (GY/WH) at pins 3 and 4. If the RCM detects a short to ground on either of these pins, it w ...

    Audio Unit
    Torque Specifications Audio System The Mustang is available with the following audio systems: M100 CD AM/FM CDX6-AM/FM with six CD in-dash MP3 single CD AM/FM (optional) The M100 system is equipped with four premium speakers. The CDX6 six ...

    Switch - Key-In-Ignition Warning
    Removal 1. Remove the ignition switch lock cylinder. 1. Insert the ignition key and turn to the RUN position. 2. Insert a punch in the access hole of the steering column and press the release tab while pulling out the ignition switch lock cy ...