System Diagnosis

PRELIMINARY INSPECTION

Make sure all test equipment such as test lights and voltmeters are in good working order prior to using them.

- Electrical and Vacuum Inspection Fuse
- Inspect Cruise Control fuse and replace if necessary.

Electric Brake Release Switch On Car Check:

1. Turn ignition ON and instrument panel switch to "ON-AUTO" position.
2. Connect test light (or voltmeter) to ground.
3. Probe: brown wire at brake switch connector; lamp should light (12 volts on meter), indicating proper feed.
4. Check switch adjustment with probe still at brown wire depressing brake pedal - (1/8"-1/2") should turn out light (no voltage on meter).
5. If lamp in (3) did not light, probe wire in adjacent connector cavity. If lamp lights (12 volts on meter) adjust or replace switch as necessary. If no light or 12 volts, wiring to switch is faulty, refer to wiring diagrams in this section.


Off Car Check:

1. Use ohmmeter or self-powered test light.
2. With switch plunger extended, meter should read infinity (open circuit). Test light OFF.
3. With switch plunger fully depressed, meter should indicate continuity. Test light ON.


Instrument Panel and Engagement Switch On Car Check-Switch:

1. Turn ignition ON.
2. Connect test light or voltmeter to ground.
3. Probe the three terminals of the turn signal lever cruise harness connector, first with the instrument panel switch in "OFF", then in the "ON-AUTO" position. In "Off" position, there should be no power to any of the three terminals. In the "On-Auto" position - cavity (B), brown wire, test lamp should light (12 volts on meter) and outer cavities (D), and (C), should NOT light. In the "On-Auto" switch position, the amber indicator should light.
4. Probe cavity (D), depress SET/COAST switch. Test lamp should light.
5. Probe cavity (C), depress RESUME/ACCEL switch. Test lamp should light.
6. If step (3) checks OK and either step (4) or (5) do not light, replace turn signal lever engagement switch.
7. If all electrical circuits check OK, check the other electrical circuits as well as the vacuum system.