# JD 5105 electrical trouble



## Paul Dessert (Nov 4, 2020)

Hello to all. I'm working on a JD 5105 and I suspect cluster trouble . I would like a wiring diagram for this tractor and I want to know if anyone can help? or how I can get one?. Thanks very much.


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## Tx Jim (Jul 28, 2020)

I don't have access to a wiring diagram BUT have you checked for good ground connection for instrument cluster. I think 5105 tech manual which is available from JD will have wiring diagram


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## Paul Dessert (Nov 4, 2020)

Thanks for your response. I've had the cluster out-disassembled and cleaned up and closely inspected the circuit board and wiring. I checked grounds(2) for cluster and ran a new ground for cluster. I removed ground for battery on frame-cleaned cable end and frame where it adheres to . I'm now trying to get the wiring diagram . THanks,


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## jd110 (Nov 23, 2015)

There are 2 entirely different diagrams depending on your serial number. Serial number 510008 and under has several 12 volt wires plugging into it. 510009 and above has a total of 3 power wires and one of those only has power when diagnostic/calibration fuse is installed. What exactly is the problem with the cluster? Is it only one function not working or nothing works? The diagrams I have are not formatted so I can attach them here, but I can try to answer specific questions you might have.


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## Paul Dessert (Nov 4, 2020)

Thanks so much for your effort. I had tested circuits at the cluster plug-in and I believe it would be the latter of the two you cited.
The problem is with the temp gauge . Start tractor cold and the gauge reads up into running temp immediately even though engine is cold.The temp will the increase as engine warms. It isn't running hot although gauge says it's hot.
I have installed a new JD sender and so that is off the list of possible suspects. I did then ground the wire that plugs onto sender and I swear I can't remember if the gauge pegged hot or cold but it did do one of them. I believe it went cold but I cannot be certain.


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## jd110 (Nov 23, 2015)

It does sound like you are having issue with the instrument cluster. The wire from the sending unit to the cluster is a yellow wire with number 304 stamped on it. It goes to terminal J1-E on the cluster. I would check that wire with an ohmmeter to be sure there is no resistance. If cluster has good power and ground to it and wire for sender is good with no resistance, then Cluster has to be bad. Assuming that new sender is correct and working properly.


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## Paul Dessert (Nov 4, 2020)

Yes. I know where the two cluster grounds are. Knowing number of powers would be a help. The factory sending unit behaves no differently from the original so I think I'm safe there. Thanks. I'd like the cluster wiring info for fuel gauge also if possible. Thanks.


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## RC Wells (Dec 26, 2008)

All it takes is a jump start to kill the cluster controller. My guys strip all the chipped crap out and install real gauges, end of current and future problems.


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## Paul Dessert (Nov 4, 2020)

So do you have a wiring diagram for the cluster or no? Thanks again. 
I am keeping real gauges in the back of my mind


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## jd110 (Nov 23, 2015)

See if this helps


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## danniel (Jan 12, 2021)

jd110 said:


> See if this helps


To understand this cluster scheme you have to be a professor. Is there a simpler one? I have a similar problem with my tractor.


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