Examination
1. Jack up the car and put it on stands. Locate the reversing light switch on the gearbox housing.
2. Disconnect the electrical wiring from the sensor-switch.
3. Select reverse gear with the shift lever, - between terminals 2 and 4 (to 1998) /1 and 3 (1999) the sensor connector must be conductive. Move the box to neutral and retest. This time conduction should take place between terminals 1 and 3/2 and 4 respectively. Make sure that there is no continuity between the specified terminals in all other positions of the box.
4. A defective sensor-switch must be replaced.
Replacement
1. Drain gear oil (see chapter Settings and ongoing maintenance).
2. Disconnect the electrical wiring from the sensor-switch.
3. Turn out a clamping bolt and remove the gauge switch from a transmission case.
4. Lightly lubricate the new O-ring with clean oil, seat the sensor in its original place and tighten the hold-down bolt firmly.
5. Connect electrical wiring.
6. Check up serviceability of functioning of the new gauge.
7. Pour the required amount of gear oil of the required grade into the gearbox crankcase (see chapter Settings and ongoing maintenance).
8. Lower the vehicle to the ground.