29 replies to this topic

[garrett3]

[taffy1967]

Well when you do find the voltage regulator, please provide us with some pictures and guidance as my temp gauge stopped working years ago after my coil packed in and fried it (the temp gauge shot up to hot and then hasn't moved since a new coil was fitted).

So I'd love to get my temp gauge working again and the shorting test did nothing on my Mini either.

This is a shot in the dark but has the surge somwhow? shorted out the sender on the bottom of the inlet manifold?
If its shorted to earth it will behave like this.

This circuit does go through the ecu so it may be a good idea to look into this as the car may be running the wrong fuel mixture for the engine temp.

If it thinks its cold when its not it will run too ritch and if it thinks its hot when its cold it will run far too lean.
Both are not good for the engine and performance/economy.

Well my 1990 Mini Cooper has a carburettor and no ECU. Plus the temperature gauge sender is mounted below the thermostat as on all earlier Mini models. I've tried the shorting test and even with the ignition on, there was no movement.

Anyway what is that component in the last picture?

[garrett3]

Well when you do find the voltage regulator, please provide us with some pictures and guidance as my temp gauge stopped working years ago after my coil packed in and fried it (the temp gauge shot up to hot and then hasn't moved since a new coil was fitted).

So I'd love to get my temp gauge working again and the shorting test did nothing on my Mini either.

This is a shot in the dark but has the surge somwhow? shorted out the sender on the bottom of the inlet manifold?
If its shorted to earth it will behave like this.

This circuit does go through the ecu so it may be a good idea to look into this as the car may be running the wrong fuel mixture for the engine temp.

If it thinks its cold when its not it will run too ritch and if it thinks its hot when its cold it will run far too lean.
Both are not good for the engine and performance/economy.

Well my 1990 Mini Cooper has a carburettor and no ECU. Plus the temperature gauge sender is mounted below the thermostat as on all earlier Mini models. I've tried the shorting test and even with the ignition on, there was no movement.

Anyway what is that component in the last picture?

Sorry should have realised it was a carb cooper from the avitar and siggy.
Was just in spi mode lol (been a long few days with this car)

The last picture is of the gauges themselves removed from the clocks housing as taken from the side to show the workings (ie no extra parts?)

You said your needle is in the red right?

What does it do with the ignition off? Does it drop right to the bottom?

Edited by garrett3, 25 April 2009 - 09:10 PM.

[Dan]

Ive have the original clocks here and will upload some pictures today.

The white wire to my clocks is a constant 12v... How odd? I can put lights on and run the heater and It still give s asteady 12v.
Thats Why I thought about the ecu.

I'm not trying to say you are wrong I'm just purely stating whats going on with my car.

Thanks for the pictures, don't worry nobody thinks you're trying to start an argument. I don't mind if I am wrong I'd just like to find out for sure because as you say it is odd.

Yes it's 12v on the white wire but not inside the clocks, that's what the stabiliser does. I guess you've measured that 12v with the engine off? Try it again with the engine on and it will be about 14.2. Try it again with the engine on, the battery fairly low and the lights, wipers and heater running as the car would be in the winter and it'll be somewhere around 12.5. If it really does always read 12v there then I guess it does come from the ECU and the gauges must be designed for 12v. If not there must be a stabiliser and if it's not on the PCB it must be somewhere between the PCB connection and the bimetal heaters in the clock moulding. In fact in the last photo there is a little cluster of components at the bottom right hand edge of the clock moulding as you show it that looks like it might be a stabiliser and might be wired in the way I'd expect the stabiliser to be wired.

Edited by Dan, 25 April 2009 - 09:30 PM.

[garrett3]

Ive have the original clocks here and will upload some pictures today.

The white wire to my clocks is a constant 12v... How odd? I can put lights on and run the heater and It still give s asteady 12v.
Thats Why I thought about the ecu.

I'm not trying to say you are wrong I'm just purely stating whats going on with my car.

Thanks for the pictures, don't worry nobody thinks you're trying to start an argument. I don't mind if I am wrong I'd just like to find out for sure because as you say it is odd.

Yes it's 12v on the white wire but not inside the clocks, that's what the stabiliser does. I guess you've measured that 12v with the engine off? Try it again with the engine on and it will be about 14.2. Try it again with the engine on, the battery fairly low and the lights, wipers and heater running as the car would be in the winter and it'll be somewhere around 12.5. If it really does always read 12v there then I guess it does come from the ECU and the gauges must be designed for 12v. If not there must be a stabiliser and if it's not on the PCB it must be somewhere between the PCB connection and the bimetal heaters in the clock moulding. In fact in the last photo there is a little cluster of components at the bottom right hand edge of the clock moulding as you show it that looks like it might be a stabiliser and might be wired in the way I'd expect the stabiliser to be wired.

Thanks for the advice, the 12v is solid with the engine running or not and I tried it with the heater and rear window heater as they seem to drain alot of current.

I guess there must be one in line to the clocks somewhere? BUT according the Haynes there is one within the instrument diagram for the spi just as you said there would be.

Its so odd.

Nowhere in any circuit diagram does it show any reason that the ecu should do this but it does keep me thinking.
I have cured the fault but I'm determined to find the little bugger now

Once again thanks for you help and If you have any ideas please get in touch.

[garrett3]

Here are a couple of pics of the instrument/gauges.

[Dan]

In your middle photo, on the right hand side and to the right of the adjusters there is a brass contact below where the instrument is to be screwed into the PCB. You can just see between the brass contact and a spring arm of the steel stip there are a tiny pair of copper points. That is the stabiliser. I can't quite make out how the two bi-metal heaters are joined together electrically unless it's through the PCB or another contact in the case.

This does raise some questions though. How or why is your car producing 12v with the engine running? Your alternator might need to be investigated. Does the battery charge properly? Can you measure the voltage at the battery with the engine running?

Why do several sources including some manuals suggest that the Nippon Seiki clocks have the stabiliser bonded into the PCB as an electronic component if it's really an old fashioned electro mechanical one built into the instrument itself?

That first photo, the photo I said that I thought I could see a stabiliser in previously, is that actually the tacho rather than the twin gauge?

Edited by Dan, 25 April 2009 - 10:09 PM.

[dklawson]

I've watched this thread but haven't posted since it deals with the Nippon Seiki gauges that I have no first-hand experience with.

However, the last set of pictures that have been posted REALLY caught my eye. Take a very close look at Garrett3's last set of pictures, particularly the one at the top. Do you see the brass nut with the red enamel holding it in place? Look below the nut and follow the threaded shaft down and you'll see what are basically a set of points on the end of the arm wound with the resistance wire. That is identical in design to the electro-mechanical stabilizers used by Smiths and others. In short, it looks like the NS gauges integrate the electro-mechanical voltage stabilizer IN the gauge, not as a separate piece like Smiths did.

Take a look at the stabilizer schematic I show at the top of the second page of this PDF:
http://home.mindspri...eStabilizer.pdf
Carefully look at the NS gauges, specifically the parts I mentioned above and see if they don't follow the schematic in the PDF.

With the stabilizer integrated into the gauge, you won't be able to measure 10V anywhere until you are on the "discharge" side of the NS stabilizer. Referring to the pictures above, with the gauges powered up, you should find 12V on the brass nut with the red enamel. You should find 10V on the arm (with the resistance windings) that is just below the nut. (The arm with the contact point at the end).

Thanks for posting the pictures. They are VERY informative.

[Dan]

That's why I was asking what gauge that is Doug, I can't see how that piece would fit into the casing for the twin gauges so I think it's some form of very cheaply made tacho. Unless these photos are all of the same thing and I just can't work out how they relate to each other in my head.

Actually I think I've just managed to sort it out in my mind! The part that I described as points is actually the other end of the points adjusting screw as Doug points out, is that right? I couldn't get a sense of depth in the middle photo and I thought the points were the other way around contacting the steel arm that is actually some distance above them. Doug is exactly right though about what is effectively the third bi-metal heater in the unit, that is the stabiliser and works by vibrating the points just as the Smiths type did previously. Looking at the terminals, the screw that fits through the plastic lug at the middle right of the photo connected to the brass strip and the points adjuster is the gauge supply (white wire). The steel strip around the outside of this lug is the stabiliser earth. The steel strip around the plastc lug above that is the 10v out to the other gauge and must be connected to the screw that fits through the lower plastic lug on the left. Presumably these two steel strips are connected via the steel parts that are visible in the empty gauge housing in the background. The remaining two screws through the plastic lugs will connect to the gauge senders.

Edited by Dan, 25 April 2009 - 10:54 PM.

[garrett3]

The gauges are the twins only, I did not remove the tacho.
My pictures are probably not great lol

Im glad we got there in the end

So for reference to anyone with the same problem on the later spi models the gauges them selves regulate the voltage unlike the earlier pcb or plug in types.

Ive learnt something new

Diod you guys want any more pictures of that area? I have the clocks in bits still and would be happy to post up some more snaps.

As for the volatge its def a steady 12v.

I can get 12.54 elsewhere and around 16 on charge.. I have a bigger alternator and a blue top battery.

Edited by garrett3, 26 April 2009 - 09:34 AM.

[taffy1967]

Well when you do find the voltage regulator, please provide us with some pictures and guidance as my temp gauge stopped working years ago after my coil packed in and fried it (the temp gauge shot up to hot and then hasn't moved since a new coil was fitted).

So I'd love to get my temp gauge working again and the shorting test did nothing on my Mini either.

This is a shot in the dark but has the surge somwhow? shorted out the sender on the bottom of the inlet manifold?
If its shorted to earth it will behave like this.

This circuit does go through the ecu so it may be a good idea to look into this as the car may be running the wrong fuel mixture for the engine temp.

If it thinks its cold when its not it will run too ritch and if it thinks its hot when its cold it will run far too lean.
Both are not good for the engine and performance/economy.

Well my 1990 Mini Cooper has a carburettor and no ECU. Plus the temperature gauge sender is mounted below the thermostat as on all earlier Mini models. I've tried the shorting test and even with the ignition on, there was no movement.

Anyway what is that component in the last picture?

Sorry should have realised it was a carb cooper from the avitar and siggy.
Was just in spi mode lol (been a long few days with this car)

The last picture is of the gauges themselves removed from the clocks housing as taken from the side to show the workings (ie no extra parts?)

You said your needle is in the red right?

What does it do with the ignition off? Does it drop right to the bottom?

No the temp gauge was in the red just before my original coil completely died and got replaced. Now and since fitting a new coil (some 8 years ago), my temp gauge doesn't move at all and not even whilst trying the shorting the temp sender spade connector against the block test.

So I now take it that I'll need a new gauge as it's not repairable, since there's not an actual voltage regulator that can be replaced?

Edited by taffy1967, 26 April 2009 - 10:29 PM.

[dklawson]

OK, so where are we with helping you sort this out? Your opening post said both fuel and temp gauges are reading too low. That means the output from the stabilizer is below 10V.

Your dashboard is apart. Are you the tinkering type or would you prefer to leave things as they are? Now that you know where the voltage stabilizer is, and you know where its point are, you could clean the points with some very fine wet/dry paper followed by "tweaking" the points adjustment to get the gauges to read correctly. Let us know how and if you want to proceed.

[garrett3]

I have however fixed this!!

Here goes.....

The temp gauge was reading low due to a bad earth on the engine, the temp gauge is on the underside of the inlet manifold on the spi and I ran a couple of resistance checks.

I then ground chean the arm that holds the earth strap and engine steady to the block and fitted some copper slip to keep things good in future.
The engine started sweeter and sounded much smoother and hey presto a temp gauge that reads correctly.

I then thought "but this does not solve my fuel gauge fault??"
So I set about checking the wiring that runs from the front to back and found the connector that joins the rear loom had got wet and was corroded. Spliced in some new connectors and hey presto a fuel gauge that now reads correctly.

Whilst I was there I noticed there is an earth lead that fits to the body just at the back of the ecu but an 11mm bolt, this got the same cleaning and copper slip treatment.
This seemed to help that little bit more too.

My temp is now just perfect on half and the fuel gauge is as accurate as any mini fuel gauge can be lol

This is on page one.

The problem was fixed but I was just keen to continue and find the location of the voltage stabiliser for my own sanity and to possibly help anyone else with dodgy gauges.

There was never a "blob" on my dials so I just had to know where the thing was lol

[garrett3]

Just want to thank everyone for the help I was given in getting to the bottom of this

[garrett3]

No the temp gauge was in the red just before my original coil completely died and got replaced. Now and since fitting a new coil (some 8 years ago), my temp gauge doesn't move at all and not even whilst trying the shorting the temp sender spade connector against the block test.

So I now take it that I'll need a new gauge as it's not repairable, since there's not an actual voltage regulator that can be replaced?

Sounds like the gauge is now shot, could there have been a voltage surge that killed the dials and the coil at the same time?

I have a spare set of gauges that I know work if you want them PM me and I will post them to you.