Club 80-90 Forums

Hi, looks like the voltage regulator has been bypassed on my gauge cluster. Opened it up to test the fuel gauge, cos I'm having weird intermittent readings (could be sender, who knows, that's why I'm testing). And I find this:


Which, from what I can tell, powers the fuel gauge. I think the circuit goes like this:

So. What to do about this? I imagine the voltage regulator is there for a reason.
Are original parts available? If so, what am I looking for? Does anyone have these gauges lying around, and can you give me a part number?
Are there generic parts available? If so, what specs am I looking for? I know what a voltage regulator *is*, but what is it regulating down to? 5V? 10V?

10v I believe. Does this mean your gauges are running on a fused (is that a fuse?)12 then? Also, think temp and fuel gauges are both from the voltage reg..

New ones are available- brickwerks have them, although the pins are in a different order so needs a bit of a rejig

Yes it is a 10 volt voltage regulator for the gauges.
(Fuel and coolant temperature).

The modern regulators are fitted face down as the pin order is 'reversed'.

If I was being pedantic, the wire to the voltage regulator is the black ignition live.

There is also a ground connection for the voltage regulator. (Not shown).

The red wire would be battery permanent live for a clock where fitted.

And then a 10 volt output from the voltage regulator to the gauges.

The gauges are wired in parallel -
(In your case - you have no temp gauge).
So both receive a 10 volt input and both have their own output wire in the 14 pin connector.

The fuel gauge wire goes to the gauge sender.

The temp gauge goes to the coolant shortage unit (relay like module with 42 or 43 printed on it).
(Only on water cooled.)



As for availability,
Everything you need to know is here.

https://www.brickwerks.co.uk/t3-parts/e ... ation.html

Although used parts do come up here or on ebay from time to time, if you are watching the pennies.

UPDATE - apologies, I initially half read your drawing.
I failed to realise you had an air cooled van.
I must do better next time.

As for your readings - without the regulator,
the needle deflection will vary along with the system voltage.
So chances are, the more items you have switched on, the lower the gauge reading will be...
Also the gauge may read lower at idle due to lower engine and alternator rpm.

The regulator gives a good steady 10v baseline for the gauge to work on. Assuming the battery voltage does not drop much below 11.5 volts-ish.