Gas Gauge not working on my 69 Runner

[eastyorker]

Gas gauge never worked since I bought the car. Put ground to the actual tank, nothing happens. Checked for voltage at the sending unit, found nothing.
Checked all 5 fuses in the glovebox, all good. Checked from the tabs.

Found the circuit board behind instruments, now what?

 

[Propwash]

It should be grounded from the actual sending unit itself. You're measuring ohms at the sending unit, not voltage. Gas gauge/sending unit is not a fused item. I would check to see if you're getting a reading/measurement from the sending unit. Hook up a multi meter to the stud for the wire on the sending unit. I'd use a wood dowel and see if you can cycle the float/arm in the tank (from the fill opening). Approximate ohms should be 10-80 fully cycled. If you're getting a reading there, your sending unit is working. You could check at gauge itself as well (with a helper). If that checks out...how are your other gauges working? Sometimes a bad dash voltage limiter with keep a fuel gauge from working. Is the wire from the fuel sending unit secured appropriately to the pin on the main harness hook up on the backside of the printed dash circuit board? Those pins like to crack or pop off after 40/50 years. After that, start looking at the gauge itself.

Honestly it is a really easy system with hardly any parts. You have a sending unit, a ground strap, a wire running to that printed circuit board hook up and then the gauge itself. Check those, you will find your problem. Good luck

 

[ram250098]

It could be as simple as the ground strap on the sending unit to the tank missing or rusted. Propwash is correct it is a very simple thing to trouble shoot. You can also ground the wire from the sending unit and see if the gauge moves {just leave it enough to see if she reads} if so your gauge is good.
AL

 

[eastyorker]

After taking out the dash I am cleaning all the contacts. On the voltage regulator should I have continuity on all three legs? Or how do I determine the regulator is no good? What does it drop the voltage down to?

I have continuity between the gauge and the sending unit. Also checked the Temp gauge and I also have continuity.

 

[Budnicks]

the Voltage limiter drops the voltage to 5 volts, for the gauges

 

[eastyorker]

After pulling the dash apart I found out the voltage regulator is no good. Ordered one, picking it up tomorrow.

Thanks for all the help!!

 

[6pakdave]

Look for an electronic type volt reg. Like a solid state or similar.