Should there be constant voltage through a low oil sensor?

[pchurch]

I am looking for a short or overvoltage that burned up the original warning horn in an evinrude remote control and damaged a new warning horn. I have discovered that the low oil sensor in the oil reservior has a constant 12v in it, regardless of whether the sensor's float is making contact or not. The temperature sensors have no voltage in the circuit because they don't make contact until there is a problem. I assume the low oil sensor should work the same way. Does anyone know if I'm right in assuming the low oil sensor has failed and is completing the circuit continuously, thereby damaging the warning horn and eventually blowing the engine's 20 amp fuse? Thanks for any input.<br /><br />Phildiver

 

[pchurch]

Re: Should there be constant voltage through a low oil sensor?

PS to original post. The when the low oil sensor detects low oil, the horn is supposed to sound once every 20 seconds. Also, reference previous post titled: Evinrude Warning Horn Continuously Activates.<br /><br />Phildiver

 

[clanton]

Re: Should there be constant voltage through a low oil sensor?

I missed the year and model of engine. The oil tank sensor has 2 wires, one to engine ground, the other will splice into the engine harness tan wires or run to Tach depends on year of engine and harness. Does your engine have Tach with 4 red lights and GM type connectors on control harness, both ends, or large red connector at engine?

 

[clanton]

Re: Should there be constant voltage through a low oil sensor?

The sensor wire should not have any volts.

 

[clanton]

Re: Should there be constant voltage through a low oil sensor?

Found your old post 1986 V4. The oil tank sensor has 2 wires 1 to engine ground on block the other wire plugs into tan wire on engine harness. None of the sensors wires have voltage. If you are still using the orignal VRO pump they have been upgraded from 3 wire to 4 wire to solve phoney no oil signals. If you have disconnected the VRO you should unplug VRO harness and oil tank senson. The horns go bad just setting in the parts bin, without ever being connected to anything.

 

[pchurch]

Re: Should there be constant voltage through a low oil sensor?

Clanton:<br /><br />Thank you for your advice. I have since tested an identical oil sensor system on a Johnson 70 which is working properly, and I get similar voltage readings. I'm going to try a continuity test on all four sensors in my engine to see if one has closed the circuit. The VRO pump is new, with the 4-wire update. Any other input would be appreciated.<br /><br />Phildiver

 

[clanton]

Re: Should there be constant voltage through a low oil sensor?

How are you connector meter on oil sensor, when you get voltage readings? Maby I am missing something on these systems. I will try it tomorrow with my meter and see what I get. I may have slept thru that phase of training.