Re: JCB 214 (3CX) No Forward/Reverse/Start
Posted: Sat May 19, 2018 5:45 pm
Just back from more testing and a bit more info.
My understanding of relays and how JCB implements them was wrong. Apparently JCB fuse protect their switch wires and load wires off the same fuse. I thought the fuse feeding the switch wire was simply toggling the relay off/on as this is all I have ever come across working in automotive. If CAT or John Deere wire same as JCB somebody please advise as it must be a heavy equipment thing. This 10A fuse actually supplies power to the first and second relays (mentioned above) and ultimately the reverse Hi/Low solenoids (for reverse gear).
Once I got it in my head to look beyond the relays, the solenoids became obvious. I also thought to try different gears in reverse which led me to discover reverse 2nd and 4th work but reverse 1st and 3rd blow fuse.
Next step: determine which of the two reverse solenoids are used to shift 1st and 3rd gears and then troubleshoot that solenoid. My guess now is that the solenoid has failed with an internal short but I still need to disconnect the solenoid and test for a wire short between relay and solenoid.
I took a picture from under the machine of the solenoids. Looks like three pairs, can anyone point out in the picture which pair is Hi/Low Reverse? Also any tips on how to remove? Looking into my manual now but any tips would be appreciated.
Thanks,
Brian
My understanding of relays and how JCB implements them was wrong. Apparently JCB fuse protect their switch wires and load wires off the same fuse. I thought the fuse feeding the switch wire was simply toggling the relay off/on as this is all I have ever come across working in automotive. If CAT or John Deere wire same as JCB somebody please advise as it must be a heavy equipment thing. This 10A fuse actually supplies power to the first and second relays (mentioned above) and ultimately the reverse Hi/Low solenoids (for reverse gear).
Once I got it in my head to look beyond the relays, the solenoids became obvious. I also thought to try different gears in reverse which led me to discover reverse 2nd and 4th work but reverse 1st and 3rd blow fuse.
Next step: determine which of the two reverse solenoids are used to shift 1st and 3rd gears and then troubleshoot that solenoid. My guess now is that the solenoid has failed with an internal short but I still need to disconnect the solenoid and test for a wire short between relay and solenoid.
I took a picture from under the machine of the solenoids. Looks like three pairs, can anyone point out in the picture which pair is Hi/Low Reverse? Also any tips on how to remove? Looking into my manual now but any tips would be appreciated.
Thanks,
Brian