Fuel and water guage trouble

Hello,

My water temp and fuel guages on my S3 petrol aren't working since my rebuild and rewire.

New sender s for both, new voltage regulator (have tried reusing old one incase new is dud, but no difference) and I know guages work as they did before the rewire.

How ive got it wired; live feed from fuse box to regulator then from regulator to guages. Water temp sender to water temp guage. Fuel sender unit is repro part and has three pins - 'WL', blank and 'I', assume WL is warning light (mines petrol so not connected) blank is earth to chassis and I the feed to guage.

Is this the correct wiring? Should there be more earths than just off the fuel tank sender unit?

Please help - im getting nowhere with it and have searched this forum but all the advics given in the past ive tried and yet still not working. .

Many Thanks

Have you checked the earth straps to your bulkhead and dash?

What do your gauges read if you short the senders to earth locally? ie short the temp gauge sender wire to the block and see what it reads and the same with your fuel gauge wire.

If you don't get a full swing, then it is probably that your earths are not very good, so check the earth straps for continuity.

The other thing you might want to make sure is that the wiring is right.

Get on there with a voltmeter - should be battery voltage to the stabilizer, then pulsing DC (on and off and on again) to the gauges if all is working right. If both are deceased I suspect a fault in the +12 feed to the gauges and stabilizer.

You can groundthe far side of the gauges right there at the back of the panel - if they react your problem's downstream in the engine bay or senders. i suspect however that this will not be the case.

ajr

Hello,

Thank you both for your replies. Problem sorted! It was the earths (or lack of..) from the guages, seems so simple now but i've been scratching my head for ages over it - wiring diagrams are great but I often seem to struggle seeing where the earths should go.

So for anybody who's reading this after doing a search the way it's all wired now (and working) is;

Feed from fuse box to voltage regulator, voltage regulator (live feed) to both guages. Sender unit feeds to guages and then the guages are earthed (via the round nuts with locking? washers) to the bulkhead. The three pin repro sender unit (i've seen a few threads on here surrounding the wiring of new, three pin fuel sender units) is wired with 'I' being the feed to the guage, blank pin as the earth (to chassis, though i've done mine through seat bracket mounting) and the 'WL' (warning light) as blank, because mines a petrol.

Hope any of the above makes sense.

Many Thanks

Yet another satisfied forum member!

Glad you got it sorted!

Bravo! Glad you sorted it. Gauges are a nice thing to have...