Fuel Gauge not working

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dadnova
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Fuel Gauge not working

Post by dadnova »

My fuel gauge does not register or move. I have 24 volts to the back of it when the ignition is turned on, the ground wire has good connection, more than 8 gallons in the tank.

Any idea's ?
Stekay
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Re: Fuel Gauge not working

Post by Stekay »

'76 710K
undysworld
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Re: Fuel Gauge not working

Post by undysworld »

The 24v is supplied to the gauge, and then grounded via the sensor. Ground that line, and the gauge should peg. The sender is self grounding, and often that ground is poor. Check connections and perhaps add a ground strap at the sender. Be aware that Pinz fuel gauges are often not very accurate, and it's normal to have 6 or more gallons left when it's reading empty, at least from my experience.

Edit: Or yeah, what Juergen wrote...
crcpinz
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Re: Fuel Gauge not working

Post by crcpinz »

Use the search feature. For a permanent solution you are supposed to run a grounding cable from the sender to the dash somewhere, since the ground is the tank itself. Otherwise remove tank, clean and lubricate screws and nuts, and reinstall and wait for the problem to reappear in the future.
Si vis pacem, para bellum
1976 710K
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Jimm391730
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Re: Fuel Gauge not working

Post by Jimm391730 »

It is a common occurrence that the gauges (in the dash) fail; both of my trucks needed the gauges replaced. But it is best to first check the gauge for proper operation by grounding the sender connection (the gauge should show full) and disconnecting the sender wire (the gauge should show empty) as Undysworld has said. If these do not occur, the gauge itself is faulty and will need to be replaced. If these do occur then check the ground(s) and/or add a ground wire from the sender to the gauge, check the top of the sender to see if the wire has fallen off, and lastly remove and check the sender for proper operation. I'd say that I've seen the gauge fail twice as often as all the other issues put together.
Jim M.
712W and 710M
dadnova
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Re: Fuel Gauge not working

Post by dadnova »

What is was, was the ground to the dash from the gauge holder, however it reads wrong as the tank is full to the fuel cap and gauge reads just over 1/2 tank, if I disconnect the extra brown ground wire to the front of the body, the gauge reads more 3/4 tank.
If I disconnect both brown ground wires at top left of gauge looking towards the gauge, the gauge reads full.

:shock:
dadnova
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Re: Fuel Gauge not working

Post by dadnova »

Gage not working again. On top of the tank there are two wire connections on top, only one wire connected to what appears to be the Ground side as it has a G. Can't find a second wire?

I hooked up a temp wire from the screws at the top of the sender unit to the body, nothing.

Prior it was said to run a wire to the censer wire and the gauge should peg, which terminal would this be when facing the gauge? Top left, top right, or what color wire on the gauge? Should I disconnect the wire before connecting the temp ground wire?

The only gauge I need to work and its not working. Very frustrating to say the least.
dadnova
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Re: Fuel Gauge not working

Post by dadnova »

OK, if I disconnect the two brown wires at top left of the gauge it pegs when power is turn on, these are ground wires, one goes straight to the body behind the dash, one goes to the first light on the dash hooked with another brown wire, but when I hook them up to the gauge it goes all the way to empty??????????

I took the sender unit out and I can hear the float or what ever sliding up and down in the tube.

Getting to the point of drilling the tank out and adding a glass level tube on the exterior like my tractor.
pinzinator
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Re: Fuel Gauge not working

Post by pinzinator »

I've seen a lot of Pinzgauers over the years, and most of them had inaccurate gas gauges. I look at the gauge as an indicator that there's gas in the tank, but not exactly how much- just within 5 gallons or so. Keep the spare can full, just in case.
A Pinz will go about 400 kilometers on a tank before it quits, so the trip odometer can be used as somewhat of an indication of how much gas is in the tank.
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pcolette
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Re: Fuel Gauge not working

Post by pcolette »

The sender has 2 terminals but only one is used. It is connected to the gauge. The other terminal on the sender can supposedly be used for a low fuel warning light. The sender is grounded thru its flange to the tank and then the body, which is where the problem often occurs. The ground between the tank flanges and body become corroded over time and the ground is no longer as good.
The gauge has 2 grounds, one for the internal lamp and the other for the gauge itself.
If you haven't already downloaded the color schematic, it may help you understand what the engineers had in mind.
As pinzinator said, the gauges are notoriously inaccurate whether you have the original or a newer VDO replacement.
Paul C.
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'73 Swiss 710M
'89 Puch 230GE
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rmel
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Re: Fuel Gauge not working

Post by rmel »

I love that 2'nd terminal! Saved the bacon several times. My gas gauge is custom;
Fuel and Warning LED, as well as +12V and +24V meters. Fuel is a very nonlinear reading,
sort of works. But when the LED goes on I've got 5 gallons left, nice to know in the boonies.
Strongly recommend hooking this up.

The VDO sender that SAV has is now one terminal only (sender only no idiot light). Although
their pix on the WEB site shows 2 which is not reflective of their stock. Ordered one last year
and had to return :(

You can get a new VDO 2 terminal replacement across the pond, fit's perfect.
http://www.europaspares.com/?utm_source ... 6-80629649

If your looking, send me a PM and I can dredge up the VDO SKU.
dadnova
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Re: Fuel Gauge not working

Post by dadnova »

You might also check the sending unit. On mine the wires jumped track, sorta speak. It's a easy fix to put the wires back into place. Added tension so wires are no longer sag. No volt meter says unit is good. Because of that I think the gage is now bad, as it heated up and wire came off, I'm thinking burned up resistor. Working on it.
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