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Off the top of my head I think the sensor on the block is a low pressure and the one near the alternator is high

If its beeping when the revs are high like climbing up a hill or carrying extra weight I'd say it could be the sensor near the alternator (high)

Very easy to replace no need to take it to the garage to have them unscrew one thing ✌
 

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Same for me, did you resolve this ?
Also interested in this - anyone have any recommendations for someone in Essex/London area who could fit a manual/mechanical gauge to a T5 2.0l Diesel?

I have an intermittent oil pressure warning (very alarming - "stop driving immediately" etc) which I am 90% certain is an electrical issue, but for peace of mind would love to see what it says the oil pressure is doing when the light comes on...

Also as a second noob question: If during a 100 mile trip, the oil pressure warning light comes on for 1 second and then goes out (before you even have a chance to pull over/stop the vehicle) - this must strongly imply electrical vs mechanical fault with the vehicle, right?

Have had it at the garage for last 2 weeks and they've checked the pressure (fine), replaced the sensor - took for a test drive and the light came back on twice during the trip.

They then affixed a mechanical gauge and test drove it again every day since to try to get the light to come on to compare to the gauge but it hasn't since :-/ Don't really want to start forking out more money to investigate until I at least know whether it's mechanical or electrical issues I'm looking for.....
 

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My 1999 T4 AJT has just started the oil light nonsense .It appears to be one of the later types with (i think ) only one pressure sender ,attached by a yellow wire on the front of the block near the bottom and close to the oil pump .Comes on at 2000 revs .Have ordered a new sender which fifty /fifty will put it right .Have also ordered an oil pressure test gauge kit from Amazon to see what the actual pressure is .From online research it should be 2 bar at 2000 revs .Pretty sure this is the case as this is certainly not a worn out engine .Had it ten years and has had plenty of oil changes with good oil and has done 150,000 miles and is all original .Will post my findings when I have the kit.We shall see!
 

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Correction .It is a 2000 AJT .Took out the old sensor (24mm deep socket ),easy to get at .Connected the oil pressure gauge with one of the several adapters supplied and started up .Showing 2bar at tick over and 4bar at 2000 .Could rev up to nearly 5bar .So the the oil pressure is excellent .
Fitted the new sensor .You need to press really hard on the plastic clip in the yellow wire connector to get it to engage .Tested and no beeps or lights so all good .A test gauge is about 20 quid and well worth it .Would be very useful to test the engine of a potential purchase .If the emissions are good and the oil pressure is good then the engine must be in good condition .
 

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Hi all,
I have a 2001 1.9TD ABL which has 1 sensor/switch on top of the oil filter housing, it only beeps when warm and around 1800 RPM - if I connect the wire to the negative terminal of the battery the buzzing stops. Does this indicate a faulty sensor?

Thanks
 

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Either faulty sensor or actual low oil pressure .By connecting the wire to ground you are doing what the sensor does when it reacts to sufficient oil pressure .You have in fact proved that your instruments are working correctly .Mostly likely the sensor is faulty .Dont know the correct one for this model but they are colour coded and cheap enough .Try one .If it works fine .If warning with new sender then may have low pressure .I bought an oil pressure test kit from Amazon at about twenty quid and checked that the oil pressure was good
 

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Hello all. I have recently developed a problem with my van where the oil pressure light and buzzer comes on, and stays on as soon as I reach mid level revs. I've taken it into a garage where its been tested and shown that the van doesn't have a problem with oil pressure, and both of the sensors were apparently working fine. The mechanic suspected a problem in the electrical side of things, and didn't seem interested in taking it any further so now I have it back.

I've preformed the following test:


A. To test the high pressure sensor circuit and wiring (sensor for this is on the oil filter housing):

1. Disconnect the wire to the high pressure sensor on the filter housing and let it float (un-connected).
2. The oil buzzer should now come on and indicator will flash when the van engine speed is above 2000 RPM.
3. Now connect the yellow wire to ground and rev the engine past 2000 RPM… the buzzer should not sound at all.
4. If you fail either of these tests you have sensor issues, wiring, alternator wiring, or instrument cluster issues.

To test the sensor itself:
A test light between the sensor and the positive battery terminal should be 'off' at warm idle and come 'on' as you rev to 1800-2k RPM, if the sensor on the flange is working properly. If the buzzer still sounds with the wire to the sensor grounded the problem is most likely the wiring to the instrument cluster.
Steps 1 & 2 I can't test as the buzzer always comes on regardless at the moment. On step 3 the buzzer and light doesn't sound.

The following test, where you test the sensor itself I have performed with the a multimeter, and I read 0v at idle, and 0v at higher revs, and 12.5v when the ignition is off.

Does this all prove that the mechanic was mistaken and the sensor is at fault?
 

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When oil pressure is sufficient at revs above about 2000(or a bit less),the sensor completes the circuit ground and the light and buzzer goes off .You are having that effect at step three .It seems the sensor is not opening to ground .Not sure what you mean by your last test .
 
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