Fuel Gauge Resistance - LPG showing incorrect levels on dash

[brichman]

Hi Guys,

My apologies if this question has already been asked, but I did my best to have a look and I couldn't find anything!

I've got a GN Sigma wagon, its on straight gas. Its got an APA industries tank with a 40(empty) to 282 (full) ohm fuel sender thing. It has been retrofitted into the dash gauge, and it never goes past 1/2, and reaches empty when the tank is 1/2 full. I assume this is something to do with the resistance of the dash gauge not matching the one on the tank.


The question is, does anyone know, or know how to measure, the values of resistance that are of the fuel gauge on the cluster? Once I know this, I should be able to either get a new sender, or make a conversion circuit, to make this somewhat more accurate.

Thanks for your help in advance,
Ben.

[brichman]

Whoops, buggered that one up, sorry! The tank sender is 282 ohm (empty) to 40 ohm (full).

[Belial]

Where are you based?

I took my old XB Pano to a local LPG place and they wired the tank up to my factory XB GT dash and it was spot on!

[Superscan811]

Most of the older aftermarket LPG guages I have seen use 2 variable resistors, 1 to set the high level and another one to set the low level, along with a jumper for direction.

What you need to do is measure the VOLTAGE at the gauge. this will better help with making a circuit, if your gauge isn't adjustable.

If you have it, a variable power supply would be perfect to check what voltage the gauge is expecting.
Check the voltages it is currently getting as a good starting point, just remember, the gauge usually requires a minute to "settle".


Cheers.

[brichman]

Where are you based?

I took my old XB Pano to a local LPG place and they wired the tank up to my factory XB GT dash and it was spot on!

I'm based in SA, I think there is a mob called ProGas that might be able to help me out!

Most of the older aftermarket LPG guages I have seen use 2 variable resistors, 1 to set the high level and another one to set the low level, along with a jumper for direction.

What you need to do is measure the VOLTAGE at the gauge. this will better help with making a circuit, if your gauge isn't adjustable.

If you have it, a variable power supply would be perfect to check what voltage the gauge is expecting.
Check the voltages it is currently getting as a good starting point, just remember, the gauge usually requires a minute to "settle".


Cheers.

See, the issue is that its been wired up to my petrol gauge on the dash, as I dont have any capacity for petrol anymore. I assume all I need to do is get an LPG sender that matches (whatever?) the stock fuel sender in a sigma was... However, this, i have no idea.

[Belial]

I'd suggest calling "progas" then.

Like I mentioned, the mob that did mine wired the tank to my gauge.

Had not been done when I bough the car..