Oil sensor alarm

[pearsonw]

I have a volvo 4.3GLa that has an issue with the oil sensor alarm above the oil filter. The sensor works fine while engine is being started and running. After shutting down engine the sensor will go into alarm about 5 hours later with the key in the off position and no power to engine. I have replaced ignition switch, alarm and the sensor and still have the same problem. If sensor is disconnected the system will still drain the battery. With engine running the oil pressure gague reads between 40-60 PSI. Any ideas where the problem may be located.

 

[Don S]

Re: Oil sensor alarm

If sensor is disconnected the system will still drain the battery.

Then it's probably not that sensor causing your problem.

If you disconnected the wire from the oil switch and it still worked, then it completely eliminated the switch itself as the problem.

With the ignition switch off, do you have power to the purple wire on the ignition switch?
If not, check any of the purple wires on the engine, do they show any voltage?

To test with a meter, you must have the meter on DC Volts, the red test lead on the point being checked and the black lead on a good clean ground. Battery negative terminal is best.

 

[pearsonw]

Re: Oil sensor alarm

Don,
I have power to the purple wire on the ingition switch. I disconnected the lead to the oil senor switch and the alarm stopped. I put the lead for the oil senor to ground and the alarm starts again. If the boat is started with the switch connected the alarm stops and gauges show 40-60 PSI. The problems is the after the engine has sat idle for 4-5 hours the alarm will start by itself.

 

[Don S]

Re: Oil sensor alarm

With the key off, you shouldn't have power on the purple wire at all. If you do, something is either wired wrong, or a couple of wires are shorted together. How do you shut the engine off if you always have power on the purple wire?