Electrical System
- Check fuse and connector. Unplug electric brake switch connector at switch. Connect ohmmeter at two terminals on brake switch. Ohmmeter must indicate no continuity when pedal is depressed and continuity when pedal is released. Replace switch if necessary. Check clutch release brake switch in same manner.
- Unplug engagement switch connector at electrical wiring harness connector. Connect ohmmeter between terminal No. 1 (brown wire) and terminal No. 2 (blue wire). Continuity should be maintained until switch is pressed all the way in. Connect ohmmeter between terminal No. 1 (brown wire) and terminal No. 3 (black wire). No continuity should be shown except when button is depressed halfway. Connect ohmmeter between terminal No. 2 (blue wire) and terminal No. 3 (black wire). With button released, no continuity should be shown. With button depressed partially and fully, continuity should be shown.
- Disconnect engagement switch wire harness connector from main harness connector. Connect ohmmeter between brown-white striped wire in main wiring harness and ground.NOTE: Ensure regulator is well grounded to chassis.
Ohmmeter should read 42-49 ohms. If resistance is not within specifications, disconnect the connector from regulator and measure resistance of brown-white striped wire. Resistance should be 40 ± 2 ohms. If not within specifications, replace main wiring harness.
- Measure solenoid coil circuit resistance between hold terminal and ground. Resistance should be 5-6 ohms. A reading of less than 4 ohms indicates shorting of coil circuit and a reading of more than 7 ohms indicates excessive coil circuit resistance. Either high or low condition indicates replacement of regulator assembly. Check white wire of main harness from engagement switch to regulator for continuity.