The oil pressure sender relays to the dash gauge the oil pressure in the engine.
- To test the normally closed oil lamp circuit, disengage the locking connector and measure the resistance between the switch terminal (terminal for the wire to the warning lamp) and the metal housing. The ohmmeter should read 0 ohms.
- To test the sending unit, measure the resistance between the sending unit terminal and the metal housing. The ohmmeter should read an open circuit (infinite resistance).
- Start the engine.
Once again, test each terminal against the metal housing:
- The oil switch terminal-to-housing circuit should read an open circuit if there is oil pressure present.
- The sending unit-to-housing circuit should read between 15-80 ohms, depending on the engine speed, oil temperature and oil viscosity.
- To test the oil pressure sender only, rev the engine and watch the ohms reading, which should fluctuate slightly (within the range of 15-80 ohms) as rpm increases.
- If the above results were not obtained, replace the sending unit/switch with a new one.
REMOVAL & INSTALLATION
- Disconnect the negative battery cable.
- If necessary for access, raise and safely support the vehicle.
- Detach the sensor electrical connector.
- Remove the sensor.
- Coat the first two or three threads with sealer. Install the sensor and tighten until snug. Engage the electrical lead.
- Carefully lower the vehicle.
- Connect the negative battery cable and fill the engine with oil.