20 replies to this topic

[Mini_Rob_Cov]

I bought my car about 3 weeks ago and the petrol guage doesn't work properly. Sometimes the needle doesn't move, sometimes it moves to just under quarter full, and sometimes (very rarely) reaches half full.
I read other posts with similar problems and tried the fixes with the fuel sender, with no luck. I put a new fuel sender in today and still the same.
Also my speedo reads 10mph slower than actual speed so could it be a problem with my guages?

[scottyegg]

have u changed the wheels on your car bigger or smaller? this can offset the speedo the fuel guage im not sure about :S try cleaning the connection ?

[dklawson]

The speedometer error will be unrelated to the fuel gauge problem. The speedo is mechanical, the fuel gauge is electrical.

As mentioned above, if someone has swapped the final drive in the gearbox or you are running different sized wheels/tires than the car was built for, the speedo will read incorrectly. Before you jump to that conclusion, drive a known distance and record your odometer readings, then compare the values. The odometer is gear driven. If the odometer matches the known distance you've driven, this indicates the speedometer gearing is correct but that you have a calibration problem with the speedometer.

Back to the fuel gauge. What is the temperature gauge doing while the fuel gauge reads low?

[Mini_Rob_Cov]

The temperature guage usually reads just below the half way mark. Not sure if it is reading correctly though.

And the speedo may be off due to the wheels, it's a 94 mini 35 with 12" deep dish, but i think the 35 came with 12" wheels as standard

[taffy1967]

So have you done the paper clip test and connected the two fuel tank spade terminals together with said paper clip and then switched the ignition on and checked to see if the gauge hits the full mark?

If it does then you're tank sender/float could be to blame, but if it still stubbornly refuses to move all the way, then it's probably gauge or wiring related.

Oh and when the wiper motor park-switch failed on my sisters Mini (it makes the wipers park themselves), her fuel gauge went haywire too. But if I sprayed WD40 at the rear of the wiper motor (over the park-switch), the gauge then magically read correctly for a time.

Replacing the pesky park-switch solved the problem once and for all and I had a similar problem when my park-switch packed in, but in my case I got a blowing fuse instead.

[taffy1967]

The temperature guage usually reads just below the half way mark. Not sure if it is reading correctly though.

And the speedo may be off due to the wheels, it's a 94 mini 35 with 12" deep dish, but i think the 35 came with 12" wheels as standard

Yes it came with 12" Minilite style alloy wheels as standard.

[Mini_Rob_Cov]

Back to the fuel gauge. What is the temperature gauge doing while the fuel gauge reads low?

After taking notice of it on my way to work, the temperature guage doesn't seem to be working right either, moves just above the blue mark and stays there

Just thought i'd add, my side lights also come on when ever the ignition is on. Could be related. Short in electrics maybe?

[Jupitus]

Temp gauge and fuel gauge together MAY be a voltage stabiliser issue.... this is the device which takes the normal variable voltage of the car's system and from it produces a nice, constant 10V for voltage sensitive gauges.

Do a search on Voltage Stabiliser... some useful info knocking around.

Oh... if you work out yours is broken, I am making them these days

[dklawson]

Confirm whether or not the coolant is hot when it should be. As Jupitus said, if the temp and fuel gauge are acting up together it can be an indication of a faulty voltage stabilizer. Nice of Jupitus to offer you one.

[taffy1967]

But a Mini 35 like all post 1985 Minis will have Nippon Seiki type instruments (as opposed to the good old Smiths variety) and therefore there will be no replaceable voltage stabiliser plugged into the back.

If you're temperature gauge is actually moving then that's a good sign (mine hasn't for years), so try the paper clip test on the coolant temperature sender spade (mounted just below the thermostat), so remove the spade and use the paper clip to short it against the block or cylinder head. Then with the ignition on you're temperature gauge should hit the red/hot mark.

If it does then simply replace the temperature sender, if it still stubbornly refuses to move then it's probably gauge or wiring related.

But like I said earlier, if you're wipers don't park by themselves then replace this pesky little bleeder because it will cause all kinds of electrical mayhem when it fails and the gauges run on the same circuit: -

[taffy1967]

As for the sidelight issue, here's the wiring colour connections at the front of the car behind the grille: -

Earth is the Black wires
Sidelights are Red/Red with Green
Headlights are thick Blue with Red
Main Beam thick Blue with White

So check those pesky bullet connectors, although you may just need to fit a new headlamp switch and this might come in useful too: -

Standard 4 fuse box mounted on the bulkhead: -


1 1-2 35amp Brake Lights, Reverse Lights, Direction Indicators & Rear Screen Demister.

2 3-4 25amp Horn, Headlamp Flasher, Brake Failure Circuit & Radio Memory.

3 5-6 25amp Heater Blower Motor, Windscreen Wipers, Washer Motor & Instruments.

4 7-8 15amp Side & Tail Lights, Panel Lights & Instruments.


1-2 These circuits only operate with the ignition switch at position "II".

5-6 These circuits only operate with the ignition switch at position "I" or "II".


In-Line Fuses situated behind air-filter on the bulkhead: -


15amp - Purple/Orange Wire
Hazard Warning & Interior Lamps


15amp - Brown/Orange Wire
Dim-Dip Lighting


10amp - Blue/Orange Wire
Rear Fog Guard Lamps


15amp - Blue/Red Wire
Auxiliary Cooling Fan

Edited by taffy1967, 06 September 2007 - 01:11 PM.

[Jupitus]

But a Mini 35 like all post 1985 Minis will have Nippon Seiki type instruments (as opposed to the good old Smiths variety) and therefore there will be no replaceable voltage stabiliser plugged into the back.

Oi! Stop sabotaginh my sales.... err......

Of course! How silly of me

[taffy1967]

But if someone would like to devise a way to get my C**p Nippon Seiki temperature gauge working without me having to folk out a fortune for a replacement gauge, then I'd be very happy.

[dklawson]

Jupitus, I didn't save the link. Which chip did you end up using? Wasn't it a fixed regulator... one that did NOT require feedback resistors? If that's true, it may be possible to disassemble the Nippon gauge cluster enough to splice in the chip you found. No guarantees... but it might be possible.

[Jupitus]

Jupitus, I didn't save the link. Which chip did you end up using? Wasn't it a fixed regulator... one that did NOT require feedback resistors? If that's true, it may be possible to disassemble the Nippon gauge cluster enough to splice in the chip you found. No guarantees... but it might be possible.

Indeed... very simple really, albeit quite fiddly... obviously my advanced knowledge of manufacturing techniques (aka my having spent about a week trying different methods of getting this into a loom-able form!! ) is what makes it a premium product *ahem*

http://rswww.com/cgi...r...e&Nr=avl:uk

ooo nasty linkeh - hope it works!