1982 FJ40 - Troubleshooting Fuel Gauge (1 Viewer)

[overton]

I have a 1982 FJ40 that the fuel gauge is not working on. I pulled off the access plate to see if the sending unit was connected and it was. Then I grabbed the tester light, grounded it and touched it to the connector that plugs into the top of sending unit to see if I had 12v there. The light started blinking intermittently and the fuel gauge moved up so it appears the gauge is working.

Bad sending unit perhaps? Any suggestions, tips or guidance would be appreciated.

Greg

 

[thebigredrocker]

Sounds to me like the ground for your sender isn't doing its job. When you put your test light on + and grounded it, you completed the circuit which perhaps allow the signal to be sent to your fuel level gauge.

 

[bj40green]

So far, so good. The "blinking voltage" is correct and the gauge needle moves.
Check the White/Black wire (ground) for continuity to chassis.
Check the sender for working properly. Connect your meter to it in the ohm position and move the lever.
Reading should be between 17 (full) and 120 (empty) ohm. This is best done with an analog meter.

Rudi

 

[overton]

Looks like the sending unit had two spades on it and one is gone.

 

[Poser]

What do the ends of the wires to the sending unit look like?

 

[overton]

Like this

 

[thebigredrocker]

Assuming you don't want to cut your OEM female plug off or buy a new sender if the present one still has life. What if you take a short chunk of wire, crimp a male spade on one end and a small ring terminal on the other. Stuff the spade in your OEM plug, test that when grounded your sender works. If so, remove one sender screw, scuff the surface and sandwich the ring terminal between the screw and sender body.

Also you might be a good idea to scuff up your OEM terminals

 

[bj40green]

Yep, that one is gone.
You'll need to order a new one. 83320-60051 (the one on the bottom).

Rudi

 

[imyahucklbrry]

Not even in the ball park as others tech wise with my comments on this (always grateful for the wealth of knowledge here) but... one of the many 'heads up' I received from the PO of my '82 was concerning the fuel gauge: "don't trust that there gas needle; just fill er up when it shows half way"

It would never show as being full no matter how much I topped it off... Once I finally got the access panel off, I found an impressive dirt dauber residence - After a good cleaning with brush and electrical parts treatment, it has been spot on.

 

[overton]

Thank you Mud!

 

[overton]

Ran a ground from the female connector to one of the screws as suggested. Need to test for accuracy but it seems to work. Thanks for all the help.

 

[thebigredrocker]

Nice!

 

[overton]

Thanks BigRed

 

[FJ62CRZR]

I have a 1982 FJ40 that the fuel gauge is not working on. I pulled off the access plate to see if the sending unit was connected and it was. Then I grabbed the tester light, grounded it and touched it to the connector that plugs into the top of sending unit to see if I had 12v there. The light started blinking intermittently and the fuel gauge moved up so it appears the gauge is working.

Bad sending unit perhaps? Any suggestions, tips or guidance would be appreciated.

Greg

Can you tell me exactly where the access plate is for the fuel sending unit? Mine is a 1980 FJ40. I believe 1979-1983 are the same. Photo would be great if you Have, Thanks, RJ

 

[overton]

If you have a stock FJ40 it will be a square plate with rounded corners and two screws holding it direct behind the rear seats in the center of the cargo area.

 

[Brewsterfire]

I have an early sender connected to a new dash with fuel guage and getting no reading. Do i need the newest sender? Or is it the original voltage regulator giving problems?

 

[Nhirsch]

View attachment 1638160 If you have a stock FJ40 it will be a square plate with rounded corners and two screws holding it direct behind the rear seats in the center of the cargo area.

Hi
I took off my sender to check that it works well with resistant meter (11.8 - 124 ohm). My question is in which direction the arm should point when I install it back? When I took it off the arm was pointing towards the front but I'm not sure PO did it right. Can someone confirm this is the right direction? Thanks a lot.

 

[rghouse]

i have no voltage coming out of the guage wires at the sender connection?? all other guages working. wiring diagram shows straight connection to guage. ideas? bad guage?

 

[rghouse]

If the guage is shorted and works, is it possible the circuit board is busted? At wits end here. Electrical guys are over and they have done all tests on the wiring etc, and needle will not move with everything connected, but will when touching post directly it moves. sending unit is new, and both it and old one send voltage.

 

[Nhirsch]

If the guage is shorted and works, is it possible the circuit board is busted? At wits end here. Electrical guys are over and they have done all tests on the wiring etc, and needle will not move with everything connected, but will when touching post directly it moves. sending unit is new, and both it and old one send voltage.

Could it be that your new fuel sender is wrong resistance. If you put a 50 ohm resistor instead of sender unit you should have the needle at around half a tank. If it work with the resistor then your sender unit is not correct or faulty.