Oil Buzzer .. with a twist

Hello All,

Scenario, all new oil sensors. High on the oil filter housing, low on side of head.

Side of head has the G60/G40 style Ate t piece and boss - Gauge oil temp sensor and factory low pressure sensor on there, working ok

Oil filter housing has a generic t piece, vdo dual pole sensor on top, high pressure on the side.

Oil pressure gauge working ok, up to/ over 5bar on start, drops to just under/about 1bar at idle… Sweeps up as expected. 2 and a bit at 2k rpm when warm.

If I rev it to 4k rpm/ maybe a bit over it'll set the buzzer and light off, and it doesn't go off…. Gauge showing its fine for pressure

Turn the car off to on, if moving … It'll be ok on the buzzer front, rev it past 5k light and buzzer on again, infact seemingly random rpms will set it off

I've tried it on the vdo, dual pole/ wk spade… Same scenario

Is this pointing to the L board in the speedo being a bit duff?

Are they still available… Or should I just earth out the oil buzzer?

Any other tests to go with? Gauge is always showing good numbers (new oil pump & recent rebuild, so no reason to doubt)

Cheers,
Adam

Cant remember if the white sensor is a NO or NC , so Take the wire off the white sensor and try it again, if the buzzer stops sensor.  If the buzzer buzzes then sort the wire to ground, and repeat if still buzzes it is the L board or possibly the 10V stabilizer.
 

Intersting. I just swopped instrument clusters and it's started doing exactly the same thing. I assumed it was a wiring thing as the old cluster never did it.

Will give that shot, cheers, again! Brian.

I'm thinking it's the L board, as I'm sure i can hear the buzzer ever so slightly but without the light… Something not well with it anyway

I happened on a YouTube video of someone bending the buzzer pin on the board over … Anyone done that on here? And done it for the LED light too?

I should be good for the mot next week, as it shouldn't go near 4k rpm there .. it's just annoying!

Strange it's happened to you too… Makes me think L board even more, given it just looks like a set of resistors

Cheers,
Adam.

The issue this is that the buzzer and lamp only are supposed to light up when the Oil pressure drops below 1.8bar at high rpm I think it is anything above 2000.

One input of the "L" board never leaves the cluster as it is input from the Tach. The other inputs are from the oil pressure switches and then 12v and ground.

So it is quite possible that the New clusters "L" board is flaky…. If your Water and Fuel gauge are working fine, then I don't see an issue with the Tach or a wonky 10V stabilizer, as I have had one of them go bad and cause me to loose about 400 rpm…but the fuel and water gauge was fine…  

If you haven't "Plumped" your main connector by placing a single strip of electrical tape on the plastic tongue of the clusters main connector under the Mylar it wouldn't be a bad time to do that and add a new ground to the cluster….

How to plump your Cluster connector for better contact at the pins. | Volkswagen Owners Club Forum

Mine is a mk2 cluster which is why I thought it could be the wiring. I think two of the wires switch over for the mk2. The oil light flashes all the time too.

Briano1234 said

The issue this is that the buzzer and lamp only are supposed to light up when the Oil pressure drops below 1.8bar at high rpm I think it is anything above 2000.

One input of the "L" board never leaves the cluster as it is input from the Tach. The other inputs are from the oil pressure switches and then 12v and ground.

So it is quite possible that the New clusters "L" board is flaky…. If your Water and Fuel gauge are working fine, then I don't see an issue with the Tach or a wonky 10V stabilizer, as I have had one of them go bad and cause me to loose about 400 rpm…but the fuel and water gauge was fine…  

If you haven't "Plumped" your main connector by placing a single strip of electrical tape on the plastic tongue of the clusters main connector under the Mylar it wouldn't be a bad time to do that and add a new ground to the cluster….

How to plump your Cluster connector for better contact at the pins. | Volkswagen Owners Club Forum

Yes, which I've found to be the most alarming .. well, initially.. the aux gauge shows good pressure, I believe it's less than 1.8 @ 2k and up.

Water and fuel both working ok, rpm seemingly fine too

I might well add the extra ground/earth. Never been too fond of the little wire to the valve cover… Always seemed a bit, inadequate

When you talk of taping the pad side of the plastic tongue, which side - it might be obvious, but without it in front of me I'm struggling to visualise

Ahh I'm sure there might well be a difference from mk1 > mk2. Although maybe not so big?

I think the flashing light from start is the low pressure switch .. should go out when past 0.3bar/ low pressure or once started, then the high takes over from 2k and alerts at less than 1.8bar

Perhaps the mk2 wires are another way around to the cluster, via the plug..

Cheers,
Adam.

adi3390 said

When you talk of taping the pad side of the plastic tongue, which side - it might be obvious, but without it in front of me I'm struggling to visualise

He left a link to a how-to at the bottom of his post. You can see the white tape through the mylar here:

It's on the other side to the face you can see so that it pushes the contacts tighter against the connector.

the_whip said

adi3390 said

When you talk of taping the pad side of the plastic tongue, which side - it might be obvious, but without it in front of me I'm struggling to visualise

He left a link to a how-to at the bottom of his post. You can see the white tape through the mylar here:

It's on the other side to the face you can see so that it pushes the contacts tighter against the connector.

Ah yes, hadn't quite zoomed the pic .. must help isolate the strips better.

Cheers for that

adi3390 said

Ah yes, hadn't quite zoomed the pic .. must help isolate the strips better.

Yeah, I couldn't work it out the first time either  

It seems mine was just the mk2 wiring. 0.3 & 1.8 bar are switched for the CE1 mk2 clocks. So mine works okay now.

On the off chance it might be of use to you, I tried neither connected, just 0.3, then just 1.8. None of those reproduced the issue  

If you disconnected the White sender on the oil filter flange and the issue went away, then I would suspect the sender.  

A good thing to know is to use a Mechanical Oil pressure gauge to test your system as in place it on the side of the head to get accurate readings.. Then I usually pull the white sender and check it at the output of the pump.. Once I know  it is mechanically correct, then I make note of the two readings and make a mental note of where the oil pressure is on my gauge so I know that when it shows this or that Bar It is actually at this mechanical value..I loved the MG's and Frog-eyes of my youth and the mechanical Smiths gauges….No flaky electrics on those….

Update to this chaps,

Added the extra earth behind the cluster, and the tape etc - No change on the 4k rpm alarm, with individual sender

Switched over to the dual pole vdo sender, same again, 4k it cuts on.

Earthed the sender wire to the body of the car, same again! @4k

I'm guessing that suggests the 'L board'?  Although why 4k rpm?

The annoying low noise buzz has gone… Lubed up the speedo drive and added some spray ptfe to the cable.

Any further ideas guys, or is it a matter of getting a new L board/ removing it ? Modifying it?

Cheers
Adam.

Well I would suspect the "L" board if Mechanically your oil pressure is good.

To update this slightly, I've a spare board out of a spare set of base clocks… Boards look quite different though?

On another note, on our recent hot day … No oil light, revved all the way around to 6k and a bit. Oil buzzer plate and spring also removed .. so just an almost liveable led

Did you ever solve this?

the_whip said

Did you ever solve this?

Sure did, it was the board itself. Doesn't happen on a hot day, only a cold one.. so solder or capacitor issue somewhere

Have a spare now, but just disconnected the buzzer spring/ plate and left the led

I've the manual guage so know the pressures aren't low

Okay. Thanks a lot.