Instrument Lighting Inoperative

Use this fault-tracing procedure if all the instrument panel gauges are working.

Sources of Fault:





- Open-circuit in lighting ground.

Start fault-tracing at step 1, below.





1) Checking Indicator Lights:
- Ignition on.
- Switch headlights on.
- Turn instrument lighting control (rheostat) to maximum.
- Check if dipped rear (fog) light, main beam and flasher indicator lights come on.

If indicator lights come on there is an open-circuit in the lighting ground lead between instrument panel terminal # A17 and ground point 31/50. Check lighting ground lead for open-circuit. Checking Cables and Terminals

If indicator lights do not come on, check power supply from rheostat. See step 2, below.

2) Check:





- Ignition off.
- Expose instrument panel. (Remove Dash Board Cover) Service and Repair
- Undo instrument panel connector.
- Connect test box to cable harness connector and check ground points. Connecting Test Box





- Connect test box between instrument panel and cable harness connectors.





- Ignition on.
- Switch headlights on.
- Turn instrument lighting control (rheostat) to maximum.
- Connect a voltmeter across test box terminals # 10 (# A10) and # 17 (# A17).
- Voltmeter reading should equal battery voltage.

If reading is correct, the fault is in the bulb(s) in instrument panel lighting. Replace bulbs. Instrument Panel Bulb

If reading is incorrect there is an open-circuit in power supply lead from rheostat between instrument panel terminal #A10 and terminal 1 on rheostat 4/4.