Test I: Cruise Control Indicator Always On
- Locate cruise control amplifier. See Fig 1
. With speed control amplifier connected, test drive vehicle while measuring voltage between ground and cruise control connector C247, pin No. 4 (Red/Yellow wire). See Fig 2
. Turn cruise control switch on. Accelerate vehicle to 30 MPH or more. Press COAST/SET switch. Turn cruise control switch off. If voltage is 10 volts or more with cruise control switch on and less than one volt with cruise control switch off, go to next step. If voltage is not as specified, fault is in cruise control system.
- Turn ignition off. Remove instrument cluster. See REMOVAL & INSTALLATION
. Disconnect instrument cluster connectors C274. See Figure
. Disconnect cruise control amplifier. Measure resistance of Red/ Yellow wire between instrument cluster connector C274, pin No. 10 and cruise control amplifier connector C247, pin No. 4. Resistance should be less than 5 ohms. Measure resistance between ground and instrument cluster connector C274, pin No. 10 (Red/Yellow wire). Resistance should be greater than 10,000 ohms. If resistances are as specified, replace instrument cluster. If resistances are not as specified, repair Red/Yellow wire.
Courtesy of FORD MOTOR CO.
Courtesy of FORD MOTOR CO.