JD 8400T Ag tractor

[wardlavon]

I have a John Deere 8400T ag tractor that has the following default codes showing: CCU-46, CCU-70, HCU-52, PCU-20 and PCU-62. I'm fairly sure some of the codes are related, the problem I am having is that it will not shift out of park. If anyone can help it would be greatly appreciated, thanks.

 

[Bigfoot62]

I don't have a clue. :confused3:

:welcome: to TBN!
Surely someone will be along soon that can help you.

 

[JasG]

I would say either a short, blown fuse, or bad seat switch, low battery, maybe a charging issue. If the PTO isn't on, the one code makes me think a short, but I really have no idea without being there. Good luck.

OMAR178078: 8120, 8220, 8320, 8420, and 8520 Tractors , Block File: RX15494_00000CBCONV1_19_26OCT01.htm

CODE CCU 45, 46

Low voltage or excessive electrical load (Warning)


DE CCU 70

Operator out of seat with PTO engaged (Warning)

If not stationary PTO use, return to seat or switch off PTO before leaving cab (See Operator Presence Sensor in Operator Station Section)



CODE PCU 20

Seat switch failed closed

Have your John Deere Dealer repair as soon as possible


ODE PCU 62

Attempted to shift from NEUTRAL to gear with operator out of seat

Return to seat, shift to NEUTRAL and resume normal operation






Check battery (See Servicing the Batteries in General Maintenance and Inspection Section)

Please let us know what you find.

 

[wardlavon]

Thanks guys, will be at farm tomorrow and check - bet I left PTO switch on but will let you know.

 

[JasG]

Thanks guys, will be at farm tomorrow and check - bet I left PTO switch on but will let you know.

I would still think it might be the seat switch. I think that would prevent you from shifting even with the PTO on, although you may very well have left it on and is the reason for the other codes.

 

[wardlavon]

The PTO was not on, replaced seat switch - didn't help, found short in wiring running to seat switch. Transmission shifts fine now, thanks JasG so much for your help.

 

[JasG]

Glad I could help, thanks for letting us know what the issue was.

The combination of alarms was why I thought short to begin with. I was surprised Deere had the codes online, I've looked before and more often than not, can't find them.