Full calibration of 4310 fails at final step for reverse

[tennessee zim]

I am new to the forum but wanted to ask if anyone had done a full calibration on a JD 4310. I had to replace a reverse potentiometer so went ahead and did a cal on the forward and reverse potentiometers and then did the throttle and a full cal moving the fuse and all per the manual. It all worked perfectly till the very last step when I could not get the reverse to work (ie forward, reverse potentiometer and throttle and forward drive circuit cal'ed) but reverse would not move even though the tractor is up on blocks and I waited 25 seconds. I wondered whether anyone had come across this and what did they do

I have the checklist of electrical checks and then the dreaded pump failure diagnosis but thought if it was just the pump then forward wouldn't work either.....any thoughts?

 

[mfreund]

Have you checked the voltage operating at the replaced potentiometer? It sounds like the reverse potentiometer needs calibrated. Calibrate it and retry the sequence.

 

[tennessee zim]

Thanks for your reply. I have managed to solve the problem and here is what happened. Initially as I said I would get to the reverse drive cal and it would not cal and would only give me the light sequence for the final step whichit would not do. I again double checked all the voltages at TOT BOT and throttle and they were still reading fine then I re tried the cal again and it went through all the steps until the final and then it gave me two codes one for the reverse drive cal and the other for the flywheel sensor which had been replaced. I then decided to follow that wire from the flywheel sensor and then deep under the seat found where a rat presumably had sharpened his teeth on it and cut the wire. I had to totally take off the seat and the seat post and got to the wire which I spliced and covered and after reassembling the tractor the cal raced through and NO ERROR Lights and the tractor works fine. One fellow mentioned that JD goes out of their way to try and make these tractors dependent on special tools for service and I think he is right.....thank goodness for a forum like this where you can get excellent help from fellow owners without having to haul it to a dealer who probably knows much less than the collective intelligence of this forum.Again, thanks for your reply

 

[mfreund]

That is fantastic!! I am glad it was easy to find. The potentiometers are proving themselves to be reliable, but the wiring seems to be the weak link.


As for the dependent tools, ALL manufactures are doing this. I think as these 4x10 tractors age it will get easier as more people understand and have worked on the electronic systems. When I first had to do my recalibrate, I felt all alone. Now there are more people with knowledge and understand the system.