LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Ford >> 1978 >> Fiesta >> Repair and Diagnosis >> Electrical >> Body Electrical >> Speed Control Systems -- Automatic >> Testing >> Control Switch
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Control Switch

  1. Disconnect six-way connector at amplifier assembly. Connect voltmeter between Lt. Blue-Black lead and ground. Depress "ON" button and check for battery voltage with ignition switch on. Turn ignition off.
  2. Connect ohmmeter between Lt. Blue-Black lead and ground. Rotate steering wheel and make the following tests:

    Depress "OFF" button and check for a reading between zero and one ohm.

    Depress "SET" button and check for a reading of 646 to 714 ohms.

    Depress "COAST" button and check for a reading of 114 to 126 ohms.

    If resistance values are okay but meter needle fluctuates, remove steering wheel and clean contact surfaces of speed control ground brush and turn signal brush. If resistance readings are high, check switch assemblies and ground circuit in steering column.

scientia non olet · About LEMON Manuals