Fuel gauge not working after dash replacement

[CV35Ian]

So all done ish on dash, electronic speedo calibrated and happy, other gauges working fine but not fuel gauge.
Tried new gauge, no joy.
Bridged earth and low fuel terminals of sender and light comes on, did same with gauge wire and earth, no joy. Removed sender, Checked float sound, low fuel light bit works but no gauge change.
So what next? Tracing wires from sender to gauge sounds almost impossible as they are in the loom. Any thoughts?
Thanks
Ian

[barkerwilliams]

Voltage regulator perhaps.

Alan

[CV35Ian]

Thanks I'll have a look, might have knocked a wire off.

[CV35Ian]

Eureka moment, regulator is on back of old speedo that's in the boot as I now have electronic one - I assume that's it, so just need to reinstate that... Or do i

[trunt]

If the Temp gauge is OK then regulator probably good. As you have just been in the dash then odds are you disturbed a wire there. check you have voltage on one end of the gauge (light green from the regulator, which should have 2 light green wires on it) and ground the other end of the gauge(maybe you did that?) it should show full. Next stop is the multi plugs to the dash. Its unlikely but the next stop is the plug in the right footwell that feeds the rear loom.

[trunt]

Yes! you need a regulator.. it feeds the fuel and temp gauges.

[barkerwilliams]

"Eureka moment, regulator is on back of old speedo that's in the boot as I now have electronic one - I assume that's it, so just need to reinstate that... Or do i"

Lucky you took up with classic cars and didn't try parachuting.



Alan

[Lingen]

There's a moral to that story...

[CV35Ian]

Very true!!

[CV35Ian]

I've had email to register vehicle, however you can't fill in booking ref and it's a mandatory field, any ideas?

[CV35Ian]

OK so latest on the Fuel Gauge/Speedo set up.
So all fine as previously stated (still glad I didn't take up parachuting...), Caerbont speedo great and fuel gauge working fine until I filled up with petrol on way back from Silverstone. The fuel gauge went off the scale on the right (not a problem?...) but at that point I noticed speedo wasn't working and mileage/trip not changing.....done 80 or so miles and fuel gauge went down as it should.
Im assuming this could be to do with voltage regulator as its the only thing I've touched and as I unfastened it from the speedo clamp, gauge went back up to very full again - but still no speedo reading (power definitely OK as speedo illuminates and mileometer numbers light up).
So any ideas? speedo was working on approach to garage as its a 30 limit and I was checking speed.
Not sure why a voltage regulator would affect an electronic speedo, and then cause fuel gauge to misread when not fixed onto a metal bracket.
Thanks
Ian

[jbuckl]

"Eureka moment, regulator is on back of old speedo that's in the boot as I now have electronic one - I assume that's it, so just need to reinstate that... Or do i"

Lucky you took up with classic cars and didn't try parachuting.



Alan

Ha ha.

[StagJonno]

The Voltage Reg needs an earth (via its mounting) to work, otherwise it just passes on battery voltage. As standard, it gets its earth from the speedo can, which is earthed as part of the light in the gauge.

Can't comment on your Caerbont speedo as I've not had any experience, other than to observe that its malfunction seems related to your VReg, so wiring issues are indicated.