Kubota
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Shaneard
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Check all your fuses then look for a broken wire. If not those two may be the sending unit itself.
Shaneard
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Yes, should be bolted and have a wire going to it.
sixdogs
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On the M6800 and similar sizes, there is some mystic thing that happens to make the fuel gauge go out. Mine did and I feared the hassle of a solution. Then, suddenly it started working again. Some say they have sprayed some thin oil on the back of the gauge connections and that helped.
I think when they sit for a while unused, something mildly corrosive happens at the connections and it goes away after the tractor gets used again. For me, I would wait it out and see what happens.
I think when they sit for a while unused, something mildly corrosive happens at the connections and it goes away after the tractor gets used again. For me, I would wait it out and see what happens.
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ovrszd
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On the back of the gauge there might be three terminals. A + terminal that should be 12V when the key is on. A ground terminal that should be grounded at all times. A sender unit terminal that might or not be grounded depending on how much fuel is in the tank.
How most gauges work is the tank unit is "ground". The more fuel in the tank, the more ground which makes the gauge needle rise toward full.
If yours functions like that you can ground the sender unit terminal on the gauge and it should read full. If it doesn't change, then the gauge is probably bad.
Coming at it the other way, you can do a resistance check on the sender unit wire, unplugged from the gauge, the fuller the tank, the higher ohm resistance will be recorded.
How most gauges work is the tank unit is "ground". The more fuel in the tank, the more ground which makes the gauge needle rise toward full.
If yours functions like that you can ground the sender unit terminal on the gauge and it should read full. If it doesn't change, then the gauge is probably bad.
Coming at it the other way, you can do a resistance check on the sender unit wire, unplugged from the gauge, the fuller the tank, the higher ohm resistance will be recorded.
ovrszd
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Last night I thought about this more. Not being familiar with his particular tractor, I'm not sure how the dash pod is wired. May be a PITA to figure out which wire does what if it's a multiple wired plug into a printed circuit..... Might need a wiring diagram to figure that out.
Leejohn
Elite Member
If no wires are broken then get to the sending unit. Using a jumper wire to ground out sender, if fuel gauge jumps to full then it's the sender if not it's the gauge. Do not ground it out for long, just tap it the gauge well jump up quick.