have a john Deere 9510 combine that has a brown box in it. used it for three years fine. now when i turn the combine on brown box comes on but sometimes i don't have the yield tab on the home screen. shut combine off a few times then you might have it back for a little bit a few days later then it goes away right away. any idea where to start looking. if i had to guess i assume its a wire issue and the brown box is not seeing that its hooked to a combine. i don't see any issues with the connections or wires at a glance. hoping someone has seen this or knows what harness to really dig in to looking at. any help is appreciated.