Weird electrical issue JD 3720

[Complete Turf Care]

I have a 2013 John Deere 3720 with cab. The AC has a left and right blower. Recently the right blower and the radio quit working. However, for about an hour yesterday they both worked, then quit again. Also the little air pump for the air ride seat isn't working. All the fuses seem to be good.

 

[Fuddyduddy1952]

It looks like the 4 relays are the same. If so did you try swapping them around?
Did you replace F4 fuse?
Has anything electrical been added or changed? Maybe check for rodent- chewing wires.
A bad ground can cause weird electrical problems because power takes a different path. Pull F3...the radio fuse then radio comes on? That's very weird.
If fuses & relays are good & no evidence of chewed wires I'd say a bad ground.

 

[Complete Turf Care]

It looks like the 4 relays are the same. If so did you try swapping them around?
Did you replace F4 fuse?
Has anything electrical been added or changed? Maybe check for rodent- chewing wires.
A bad ground can cause weird electrical problems because power takes a different path. Pull F3...the radio fuse then radio comes on? That's very weird.
If fuses & relays are good & no evidence of chewed wires I'd say a bad ground.

If you look at about 20 seconds into the first video, you can see what the relays are for. None of them seem to be related to my issue.

I did swap F4 and F3 fuses and they acted the same.

When this all started, I was using my tiller on some hard ground, and the whole tractor was shaking violently for a couple of hours. I was afraid the dash would fall apart.

That's why I was thinking a loose connection somewhere, but this fuse issue has me confused.

 

[Fuddyduddy1952]

Shaking could certainly cause a problem as you say. If relays are plug in it wouldn't hurt to swap around, see if theres a change. Next would be moving, wiggling leads/connectors.
I have seen bizarre things happening with a bad ground & removing the radio fuse & radio coming on is definitely weird.
Seems like vibration broke a lead (ground ?).