* A faulty gauge itself: The gauge may be malfunctioning internally.
* A problem with the sending unit: The oil pressure sending unit (located on the engine block) might be bad and not sending the correct signal to the gauge.
* A wiring issue: A break or short in the wiring between the sending unit and the gauge could interrupt the signal.
* A blown instrument cluster fuse (possibly): While there's no *specific* fuse for the oil pressure gauge, a blown fuse in the instrument cluster's circuit *could* affect it. You'd need to check the owner's manual to find the fuse(s) related to the instrument panel or gauges. This is a less likely culprit than the other three.
To troubleshoot: Start by checking the oil pressure sending unit and its wiring connections. If that checks out, you'll likely need a multimeter to test the circuit and gauge itself, or a professional diagnosis. Don't just start replacing fuses randomly.
