Fuel Gauge Testing

[Guest danny_samb]

Hi all is there a way I can test my fuel gauge with a multi meter,I have tested the sender and get a change in resistance as I move the float arm so just want to check the gauge is faulty before ordering a new one

Thanks

[maccavvy]

Hold the wire from the sender to earth.that should make the gauge move.

[Guest danny_samb]

Take the wire off the sender and touch to earth?

[Guest Ian & Carole]

Take the wire off the sender and touch to earth?

 

Yes that should give you a "full" reading on the gauge.

[Guest danny_samb]

Took the wire off and touched it on -ve of battery and get no movement from the needle

[IanS]

Is there power getting to the guage?

Depending on the regulator you should see volts at the battery connector of the guage.

Modern regulators typically give 8V here, older bimetal regulators will show switching between 0V and 12V to 14V (depending on battery charge) here.

[Guest danny_samb]

Put the multimeter on the back of the gauge getting 12v on the wire from the +ve

[Longboarder]

Most gauges will have a positive supply, an earth and a third wire that goes to a sender. All three need to be connected. Ignition may need to be on for the positive supply.

 

Nigel

[Guest danny_samb]

I was testing it direct to battery terminals

[sj-bradley]

All you need to test it with is a 3 pin potentiometer from say Maplins.

 

Get one around 12,000 ohms so that you will not put any amps through it. (12 kohms is approx 1 milliamp)

 

put the battery across terminals 1 and 3 and the gauge (signal) across 2 and 3 (3 common negative) with the gauge powered with the 12 volts to the respective points.

 

You should then be able to rotate the potentiometer varying the voltage at pin 2 from zero volts up to battery voltage and the gauge should move accordingly. (senses voltage only)

 

(That's if the gauge is a voltage sensor - do you have the spec sheet for it ? )

 

(Oh, and start with the rotating shaft turned about half way between end stops.)

 

I've just checked online and there are two types of gauge 2-wire and 3-wire.

( Google's great for that )

 

Simon.

[fry61]

I was testing it direct to battery terminals

Was there any spark or smell of burning ??

[nigelt]

Hi Danny, Assuming its a smiths gauge, check out this site, http://mgaguru.com/mgtech/electric/fg_01.htm Although my fuel gauge was not like this my temperature gauge was. Sorry this is all on one line, carriage return/line feed does not seem to be working. Nige