Check
1. The oil pressure warning light should come on when the ignition (main) switch is turned ON and extinguish a few seconds after the engine is started. If the oil pressure warning light comes on whilst the engine is running, stop the engine immediately and carry out an oil level check, and if the level is correct, an oil pressure check (see Chapter 1).
2. If the oil pressure warning light does not come on when the ignition is turned on, check the bulb (see Section 17) and fuse (see Section 5).
3. The oil pressure switch is screwed into the crankcase on the left-hand side. Remove the belly pan (see Chapter 8) and the front sprocket cover (see Chapter 6) for access. Pull the rubber cover off the switch and remove the screw securing the wiring connector (see illustration). With the ignition switched ON. earth (ground) the wire on the crankcase and check that the warning light comes on. If the light comes on, the switch is defective and must be replaced with a new one.
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18.3. Pull back the rubber then remove the terminal screw and detach the wiring
4. If the light still does not come on, check for voltage at the wire terminal. If there is no voltage present, check the wire between the switch, the instrument cluster and fusebox for continuity (see the wiring diagrams at the end of this Chapter).
5. If the warning light comes on whilst the engine is running, yet the oil pressure is satisfactory, remove the wire from the oil pressure switch. With the wire detached and the ignition switched ON the light should be out. If It is illuminated, the wire between the switch and instrument cluster must be earthed (grounded) at some point. If the wiring is good, the switch must be assumed faulty and replaced.
Removal
6. The oil pressure switch is screwed into the crankcase on the left-hand side. Remove the belly pan (see Chapter 8) and the front sprocket cover (see Chapter 6) for access.
7. Pull the rubber cover off the switch, then remove the screw securing the wiring connector (see illustration 18.3).
8. Unscrew the oil pressure switch and withdraw it from the crankcase (see illustration).
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18.8. Unscrew and remove the switch (arrowed)
Installation
9. Apply a suitable sealant to the upper portion of the switch threads near the switch body, leaving the bottom 3 to 4 mm of thread clean. Install the switch in the crankcase and tighten it to the torque setting specified at the beginning of the Chapter (see illustration 18.8). Attach the wiring connector and secure it with the screw, then fit the rubber cover (see illustration 18.3).
10. Run the engine and check that the switch operates correctly without leakage.
11. Install the front sprocket cover and belly pan.