Kubota MX5800 No throttle response

[Lat22]

I get no hand throttle response whatsoever. The lever moves up and down freely and the engine stays at idle. Does this HST tractor have a throttle cable or is it “ fly by wire”? I’ve taken the console off and can see where a throttle cable would go, but can’t find an unattached one anywhere. Please help. Thank you.

 

[lugbolt]

you can go into the meter's test mode (mode A) and you can see if the throttle sensor is actually doing anything.

It is "drive by wire".

There are several DTC's that if set, will limit throttle to basically idling only. Is your tractor 'beeping" anything, or has it in the past? Anything showing in the cluster where the hourmeter is? Say, P2294, etc?

 

[Lat22]

Thanks Lug. I had a U0075, U0081 and U0082. I went into mode B and cleared them. I tested the Acceleration Sensor voltage through Mode C and it showed normal I guess. The “check engine” light is on but no new codes. Maybe that’s throwing it into limp mode? I downloaded the service manual and it’s amazing.