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Kevin, Technician
Category: Agriculture and Farm Equipment
Satisfied Customers: 732
Experience:  Over ten years of expirence in Ag Electronics and Hydraulics
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My 6420 jd does not go forward Will go in reverse and back

Customer Question

Hi My 6420 jd does not go forward Will go in reverse and back up but when shift forward it will alarm and flash the blue ! bulb If need any more info will try my best Thanks Bryan
Submitted: 1 year ago.
Category: Agriculture and Farm Equipment
Expert:  Kevin replied 1 year ago.

Hello, my name is ***** ***** I can help you with your question.

Based on the symptoms you describe it sounds like you have a cab tractor with the electric over hydraulic left hand reverser. If this is correct then the most common cause of the condition you describe is the controller fails to detect amp draw from the forward control solenoid valve. This is most commonly caused by the wire getting snagged and damaged or simply coming unplugged from the solenoid. The below link will take you to a diagram showing the forward and reverse solenoids as #15.


If the solenoid and wiring check out good let me know and I will gladly assist you with further diagnostics as needed.



Customer: replied 1 year ago.
you are 100% correct I managed to find the fault. The plug had come out of the sensor under the transmission.
Thank you very much
Expert:  Kevin replied 1 year ago.

Great! Always good to hear when things work out. Please keep us in mind if we can be of any assistance in the future.