Fuel Guage Opposite

Apologies for another post which will probably have a simple answer!

My series 3 fuel guage is back to front. When it's full, the guage says empty, and vica versa. The only time it reads correct is when there is half a tank!

Is this just a wiring fault or something more? It did have a new fuel tank fitted about 18 months ago before I bought it.

Thanks

I think the wires going to the sender might be the wrong way round! I had this on me 90 and swapped the wires round and jobs a goodun!

thanks, but from what I can see there is only one wire! maybe something has snapped off? Should there be two?

Then the casing of the unit is the earth. Prob one of two things then - either the unit's faulty or the earth is live! - check your wiring!! I just know that having mine (which has 2 wires going to it, but as i said it's a 90) wired the wrong way round makes it read backwards!

ok, so it could simply be that the wire to the tank (or whatever if there is one!) can be swapped with that on the sender?

Yeah, if there is an obvious earth wire to the tank then try swapping em (are you petrol - don't forget to disconnect the battery first!) - although i would have thought it more likely that the chassis was the earth and the tank just earthed to that???

Personally (after just rewiring my S3 dash) , Id swap the wires to the gauge. Just unscrew the too screws that hold the gauges/dash in. Pull it out (mind the speedo cable--mines just too short!) then swap the two wires on the fuel gauge. If that doesnt work, check the voltge stabliser wires, they're well known for causing gauge problems!

But check the earthing as well, wouldnt want a spark especially on a petrol!

how else can I check the earth? The battery -ve is connected well to the engine, which then goes to the chassis.

I'll take a peek behind the dash....

Right, after looking at the wiring diagrams;

You are right there is only 1 wire that goes from the fuel tank sender, as everything else is earthed to the chassis.

So, I would simply swap the wires round on the gauge, and see if that has any effect.

The wires should be;

• From Voltage Stabiliser to Fuel Gauge LG (light green)
• From Fuel gauge to fuse/straight to tank should be GB (green black)

(The second colour being the tracer colour.)

To be honest, i wouldnt worry about the colours when swapping around, as they might have been changed on your car anyway.

Hope that helps,

Biosbill