Oil pressure light came on and has stayed on (1 Viewer)

[WhiteGluestick]

So my oil pressure light has been on for awhile now and I'm just hoping g to find some answers here. So the oil level is slightly above full (from previous owner) and my oil pressure indicator doesn't ever go above the first bar. Could it be a bad pump or could the slightly full oil cuase low oil pressure?

 

[jblueridge]

part number. 89491-36080

 

[WhiteGluestick]

I found a pic of the oil level sensor.
It looks like it has 4 or 5 bolts and a white plastic socket for the wiring to plug into.
Probably bolted on the side of the engine with just the socket sticking out.

View attachment 3323298

It's on the side of the sump it looks worse for ware so this may be the issue.

 

[jblueridge]

Get some degreaser like this stuff.
Spray it on, let sit then gently loosen the crud with a paint brush.
Do the same to its wiring.
If the engine was warmed up, the grease might come off easier.

 

[jblueridge]

When things are cleaned off, disconnect the wiring and see if the light goes out.

 

[WhiteGluestick]

When things are cleaned off, disconnect the wiring and see if the light goes out.

I've disconnected both the oil pressure sensor and the oil level sensor but the light still comes on. So perhaps it is an electrical problem like previously suggested a bad ground perhaps.

 

[jblueridge]

If there are 2 wires for the oil level sensor, I would try to run a wire between them like a short circuit.
It could be that unplugging them so there is no circuit makes the light come on.
Bypassing the sensor with some wire might turn the light off.

 

[AxelNilsson]

I was quite sure that wasn't the oil pressure light but rather the oil level light? If the oil pressure gauge is fine I wouldn't worry about the pressure.

I have a 1KZ-TE with the same light and it comes on sporadically about 9 months after an oil change signaling to me that it's time for an oil change. After an oil change it's turned off for about 9 months and so on.

When was the last time you did an oil change? Remember also that the oil changes density with temperature. When my light comes on it's about 5 minutes after the car has started from cold and goes away when the car reaches operating temperature.

 

[WhiteGluestick]

I was quite sure that wasn't the oil pressure light but rather the oil level light? If the oil pressure gauge is fine I wouldn't worry about the pressure.

I have a 1KZ-TE with the same light and it comes on sporadically about 9 months after an oil change signaling to me that it's time for an oil change. After an oil change it's turned off for about 9 months and so on.

When was the last time you did an oil change? Remember also that the oil changes density with temperature. When my light comes on it's about 5 minutes after the car has started from cold and goes away when the car reaches operating temperature.

I just presumed it was the oil pressure light becuase it was next to the guage. The previous owner told me he had just done a oil change so going off that the last change was about 5 months ago. (I wonder if the light would come on if over filled) I may try doing a oil change and seeing if that solves the problem.

 

[ToyotaMatt]

When things are cleaned off, disconnect the wiring and see if the light goes out.

I've disconnected both the oil pressure sensor and the oil level sensor but the light still comes on. So perhaps it is an electrical problem like previously suggested a bad ground perhaps.

I was quite sure that wasn't the oil pressure light but rather the oil level light? If the oil pressure gauge is fine I wouldn't worry about the pressure.

I have a 1KZ-TE with the same light and it comes on sporadically about 9 months after an oil change signaling to me that it's time for an oil change. After an oil change it's turned off for about 9 months and so on.

When was the last time you did an oil change? Remember also that the oil changes density with temperature. When my light comes on it's about 5 minutes after the car has started from cold and goes away when the car reaches operating temperature.

- perhaps we are a point of considering a different path here ?

- does anyone have a factory FSM here ?

- this will tell us how to field bench test the gauges in the dash stand alone , and confirm and verify the light is OIL level or oil pressure etc ....

- we can also for good measure field bench test in-place the Mechical BELL sending unit on engine block too



- discussion group thoughts please ...

 

[jblueridge]

It is not part of the oil pressure gauge/sender system.

 

[jblueridge]

I would do one final test. Unplug the sensor. Bend a piece of bare wire into a U shape. Hold this piece so it is touching both the metal terminals in the wired plug.
Have someone else turn the ignition key but don't start the engine. See if the light goes out. A paperclip should work. Wear thin rubber gloves.
The purple in this image represents the paperclip.

 

[Omrib]

I was quite sure that wasn't the oil pressure light but rather the oil level light? If the oil pressure gauge is fine I wouldn't worry about the pressure.

I have a 1KZ-TE with the same light and it comes on sporadically about 9 months after an oil change signaling to me that it's time for an oil change. After an oil change it's turned off for about 9 months and so on.

When was the last time you did an oil change? Remember also that the oil changes density with temperature. When my light comes on it's about 5 minutes after the car has started from cold and goes away when the car reaches operating temperature.

I have a 97 1HZ with 512k km on it.
This light comes on when engine is hot and in idle, which led me to worry about my oil pressure too.
Disassembled my oil pressure sending unit and installed a flex tube connected to a mechanical pressure gauge.
Found out pressure were well within spec for cold and hot.
Nowadays, I disregard this light as a faulty harness wire or a faulty level gauge.

But every once in a while.......I can't stop myself from worrying.....what if the dipstick was not original and was replace by PO to a longer one......what if there are metal shavings in the pan and this is the reason for the false reading from the level gauge?

Ignorance is bliss......
I would be very interested in any information outcome from this thread.

Good luck

 

[jblueridge]

I installed a mechanical pressure gauge too.
I try to ignore the factory gauge with its low reading.

 

[vega01]

Hi guys, I haven't read the whole thread, it's just a quick idea without verification about the particular truck/engine, but afaik this light is for oil level sensor and not coming directly from it, but through a so called "OK Monitor" which is a circuit for averaging or "smoothing out" the measurements of the oil level sensor over some period of time. Take a look here for example: OK MONITOR EL 89590-36130 - https://www.drive2.ru/l/570517343273223411/
I don't think the circuit diagram in this link has all the details correct, but it's more or less accurate. So I'd check this OK Monitor or Oil Level ECU for a signal going to the light.

 

[AirheadNut]

Here is the applicable wiring diagram for the oil pressure gauge and oil level light:

 

[WhiteGluestick]

Sorry I haven't responded to the thread in awhile, I still plan on getting g to the bottom of this and I'll keep you all posted on what's happening. ATM I've taken it for a few drives and it doesn't overheat nor does the oil pressure drop. So it's 100% a electrical problem. I'll look for the OK monitor and I'll try and do what jblueridge suggested and short circuit the light.

 

[jblueridge]

I just did the short circuiting thing on my 4WD switch.
I now know the switch is bad but the dash light and wiring are okay.

Let us know the end of the story when the time comes.