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I have recently bought a TF 2004, one of the problems I have found is that the fuel gauge is not working. Is this a common problem and could anyone suggest where to start please?
 

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mgf
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usually no problems with the later models, remove wire from tank sender and ground to earth, this will test the wire and gauge is working.........take out fuel sender and connect wire and move float in different angles and check gauge, if not working, it will need a new sender unit
 

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Fuel Gauge

I have found the sender unit it has four wires, I assume the two centre ones are earths therefore the two end ones are the pump supply and the fuel gauge but which are which ?
 

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Fuel Gauge

I have found the sender unit it has four wires, I assume the two centre ones are earths therefore the two end ones are the pump supply and the fuel gauge but which are which ?
I am having the same problem. I have checked the wiring diagram and can tell you that the fuel gauge wire is green and black. Will be performing tests this afternoon and will update later.
 

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Ok. I have now completed my tests and the results are interesting to say the least. I started by setting my multimeter to 2k Ohms and testing the sender unit terminals. The result was zero Ohms. I then tested the black wire with the same setting and the negative wire of the meter to ground. Zero Ohms. I then did the same thing to the green/black wire with the same result. Next I set the meter to 20v, turned on the ignition and tested the two wires. The black wire was inert but the green/black wire gave a reading of 6.5v. Next I grounded the green/black wire and turned the ignition on again and the fuel gauge moved, very slowly, from the empty to the full indication. To my mind this proves that, in my case, the fault lies in the sender unit not the wiring or gauge itself.
 

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mg_tf
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I spent a lot of time on fuel low level led, so I drilled down in the instrument and sender design

First the instrument is an amperometer, fully immerged in sylicon oil, to dump the movement, this is the reason why it is so slow.
The sender Ohms can be checked
105 Ohms empty
32,5 Ohms 1/2
5 Ohms Full
 

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Thanks for that. I knew that the fuel gauge was damped but the test data is most useful. I have just invested in a new multimeter as I no longer trust my old one. I will retest very soon and report back. Thanks again,A.
 
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