FJ60 speedo help needed (1 Viewer)

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Feb 29, 2008
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warrenton, VA
Hopefully someone has an easy solution for me. I have an 84 FJ60 with a Man-A-Fre 42 gallon gas tank. I just bought the truck so I do not have much history on it.

This is my problem. I tested the gauge like the Toyota manual says to do with a bulb and it moves up and down fine. I also tested the ohm reading from the sender, that at the time was reading 28 ohms. So I no that both work but when I turn the truck on the gauge stays at zero. Acording to the manual the gauge should read about 3/4 full with 28ohms resistance with a factory tank. I did all the checking at the plug in the rear panel before it goes through the body so I know all of the wires are good both ways.

Any help would be much abliged. I have put about 22 gallons in it and god knows how much was allrady in there.

Thanks
 
Joined
Feb 29, 2008
Messages
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warrenton, VA
I really don't know if it is the stock sender or if it has been extended. It was done by the PO. I would rather not have to drop that bahemoth of a tank.
 
Joined
Feb 29, 2008
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warrenton, VA
with the Man-A fre tank in there the sending unit is not under the access panel. I tetsed the sending unit according to the toyota manual. It all checks out. I tested it at the plug by the wheel well.
 

rchalmers3

I speak Toyota
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I tested the gauge like the Toyota manual says to do with a bulb and it moves up and down fine. I also tested the ohm reading from the sender, that at the time was reading 28 ohms.

Ok, so a bulb moved the guage and you are seeing 28 ohms across the sender. Here's some things to think through:

A) Where did you install the bulb for testing the meter? Hopefuly you did it as close to the sender as possible.

B) What was the resistance across the bulb you used?

C) What happens to the meter when you connect the sender wire directly to ground?

D) The meter dosen't move promptly or quickly when connected to the sender. did you give it a few minutes when testing?

E) 28 ohms sounds low, I would expect to see about a 3/4 tank reading with this resistance.
 
Joined
Mar 1, 2006
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Monument, CO
man-a-fre tank

the sender is most likely OEM out of the original tank. the senders arm should be extended about 120mm. i have the same set up in mine (man-a-fre long range tank). the 30+ gallon tanks use the OE fuel assembly and the sender, both have to be modified to work properly. you have to take into consideration that the sender is now a rough estimate of the fuel in your tank. theres a lot of room for the fuel to move and slosh, so an accurate fuel reading is almost a never occurance.
 
Joined
Feb 29, 2008
Messages
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warrenton, VA
I didn't even realize I said speedo and not fuel. Thank you for the correction. I tested the sender as close as I could get to it. I used the plug right were it goes through the body panel. I daisconected the plug and tested it there. I used a test light and also an 1157 bulb and some wire to test it. The 1157 read mid 30's and the test lights was about 27. I only gave it a few seconds to move. I have driven it some more since. I am going to test the sender again and see if thr resistance has changed. I am hoping yes.
 

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