Oil warning light

[Patrol'n]

Howdy all,

I've just gotten home from a drive and my oil warning light has started intermittently flickering on, then going off again.

The oil pressure sender was replaced about 6 months ago as the oil pressure gauge was not reading correctly. The pressure gauge did not show any change when the oil light came on. It doesn't blow smoke or leak oil. It was serviced about a month ago so the oil and filter are relatively fresh and I checked the level and it is spot on.

It also hasn't started making any new rattles or noises, it's never done it before, any ideas?

Thanks very much

[4bye4]

I have had oil alarms on some machinery (not Patrols) caused by the oil thinning a bit when they are hot. If you have a reliable gauge and it is not showing any issues, I would trust the gauge over the light any day. See what happens when the engine is cool.

[Patrol'n]

Thanks Tony I'll see how she goes today, I was thinking a faulty oil warning light, but since the gauge read ok, I wasn't sure.

Thinking about it this morning, perhaps I'll investigate whether the light is fed its signal from the same sender as the gauge.

[Sir Roofy]

Could be earth related or loose conection

[threedogs]

Common fault on the ZD30 motor, replace the sender
with an OEM one and as above re-do any earth straps

[Patrol'n]

Could be earth related or loose conection

I was thinking dodgy connection too, I will also have a look at the earth straps.

Noticed this morning that it appears to happen mostly on takeoff and at the same time the oil pressure is rising with the revs building.

I hate electrical gremlins...

[Patrol'n]

Progress (or no progress report), I have had the pressure checked with a calibrated test setup, and there is plenty of oil pressure, so at least the motors not in danger.

I have also removed an old crappy looking earth strap and replaced it with a heavier shiny new one and added another one for good measure.

End result is..... Still doing it the bas*#rd thing. It has seemed to settle down to only doing it when the aircon is switched on while idling and the thermo comes on??? If I give it just the lightest touch of revs, or switch off the aircon, it turns off the light. The pressure on the gauge remains consistent.

So I suppose the fix is switch off the aircon, but I really like aircon in summer 😜

At least I know it isn't the pump and now know it shouldn't be an earth strap problem. Next is to replace the sender I suppose, I've been told OEM ones are pricey, but what the heck, might as well.

[4bye4]

Leigh, if you are getting oil light on and off when you are turning the aircon on and off, and it is changing with revs, it is almost certainly a voltage drop issue, either an earth, even though you have checked them, or low voltage from the battery. Generally when something electrical happens when another electrical switch is operated it is nearly always earth issues.

[Winnie]

Hey mate, I have a dodgy oil light in my TD42 GQ too, it has done it a few times now, the oil light will come on and stay on for a while. Both the stock gauge and my aftermarket gauge show normal oil pressure and the oil level is fine too.
Don't know why it does it.

[Patrol'n]

Leigh, if you are getting oil light on and off when you are turning the aircon on and off, and it is changing with revs, it is almost certainly a voltage drop issue, either an earth, even though you have checked them, or low voltage from the battery. Generally when something electrical happens when another electrical switch is operated it is nearly always earth issues.

Hi Tony, yep I did have that thought niggling away, I am thinking to get a second opinion from an auto sparky, intersestingly I did just have a heavier wire fitted between the alternator and battery due to voltage drop issues about two weeks ago...

Might go back and have a further chat with him.