Nissan Patrol 4x4 (Africa)

This may be of assistance on the "granade" issue on the 3lt diesel. I have a 2013 with close on 120,000km and during a long bad road trip recently my madman started beeping warnings as to oil pressure. It indicated that the oil pressure was all over the place - from 1 bar to exceeding max pressure and fluctuating wildly. I was forced to drive another 10 hours like that through alternating deep mud and rock in 4 wheel drive. Kept it slow and came to the conclusion that, since the factory light was not indicating an oil problem, oil level on dipstick was fine, no sign of overheating, it must be a short on the madman system. In addition the problem was erratic. Took the vehicle to the chap who fitted the madman some years ago. His reaction was to attach a mechanical gauge and read the oil pressure. No problem there. So he turfed the sender unit and replaced it. All good. Cost of R500.00. What is important here though is two items: Firstly the fact that the mechanic took one look at the factory unit, made by VDO, and walked to his spares to pick up a VW sender unit also made by VDO and it worked perfectly. Secondly, and this is maybe what has cost other owners a rebuild, the sender was defective YET THE FACTORY OIL LIGHT DID NOT INDICATE A FAULT. So if the sender unit fails it appears that the driver will not have any means of knowing that he may have an oil pressure problem, and he could drive like that for years. Makes madman or similar a no brainer.

Is your the CRD ?

Memory tells me it has 2 systems - will check later today and revert back:

But if I am correct:

One oil pressure sensor that sends actual pressure to the ECU - if that fails or read a problem the ECU will intervene.

One simple oil pressure switch that operates the light on the dash - if that fails or reads low pressure the light will come on

Not CRD.

I am unaware of two units. The unit replaced had a connection to the dash light.

Non CRD has only 1 yes

Thanks Rudolf - so does that mean that my mechanically challenged statement is correct? Namely that if the sensor fails on the pre-CRD the driver no longer has any functioning warning as to oil pressure? Or is there a fail-safe elsewher?

The question is: In how many ways can that oil pressure switch fail?

I have do some research....

Dungbeetle wrote: ↑06 May 2022 12:51 The question is: In how many ways can that oil pressure switch fail?

I have do some research....

2 i would guess? Open or closed. But I would also assume that it would most likely fail in the "normal" position. What I don't know is whether this switch is normally open or normally closed.

It looks like my problem is not fixed. Did about 110km towing light trailer and lightly loaded vehicle at 110Km/h on the speedo (say about 106), slowed down for a town, clutch in for downchange at speedbump and madman goes off again. Oil pressure out of range. Fluctuating from 2.4 to off the chart beyond 9bar. Quick check in manual indicates that there are two valves that may affect oill pressure? Oil Pressure relief valve and a bypass valve. Are these accessable without removing the timing gear?

OK you need to speak to Anthony about this but the 14w40 is to dirty for most of the vdo tipe riostat senders he has a new pressure electrical one that works . Most mad man's have the pressince of oil pressure like your factory one avaliable and that's what I run now . But the Vdo one doesn't work it blocks up in no time

Appreciated Tinus. Will contact Anthony during the week.