Tractor stops when throttle is applied.

[TheOldHokie]

It tries to move. I can drive very, very slow. Like it's in a sort of limp mode.

I would bet dollars to donuts its the seat switch or related wiring

Dsn

 

[TheOldHokie]

I am currently having the same issue where the tractor starts and runs no problem, but will only creep with the lightest throttle, anything over 5% and it will stall. Mine is also an L3902, i attempted to close the seat switch circuit manually and i’m still having the same issue. I’ve done a lot of searching amongst the web and came across this post which seemed to maybe point me toward an HST sensor… curious if you ever solved the problem. My next step was going to check for continuity from the seat sensor wires to the terminals on the Main Ecu, assuming maybe the wires broke somewhere or a mouse chewed them possibly.


Any help is very much appreciated.

I would bet dollars to donuts its the seat switch or related wiring.

And JFYI you are not applying throttle. The HST pedal is a "GEAR SHIFT". When you rock it forward you are upshifting the transmission. The throttle is a lever on the dash.

Dan

 

[North Idaho Wolfman]

I am currently having the same issue where the tractor starts and runs no problem, but will only creep with the lightest throttle, anything over 5% and it will stall. Mine is also an L3902, i attempted to close the seat switch circuit manually and i’m still having the same issue. I’ve done a lot of searching amongst the web and came across this post which seemed to maybe point me toward an HST sensor… curious if you ever solved the problem. My next step was going to check for continuity from the seat sensor wires to the terminals on the Main Ecu, assuming maybe the wires broke somewhere or a mouse chewed them possibly.


Any help is very much appreciated.

It's more likely the HST switch not the seat switch.
Read and follow the WSM on testing.

 

[whitetiger]

I am currently having the same issue where the tractor starts and runs no problem, but will only creep with the lightest throttle, anything over 5% and it will stall. Mine is also an L3902, i attempted to close the seat switch circuit manually and i’m still having the same issue. I’ve done a lot of searching amongst the web and came across this post which seemed to maybe point me toward an HST sensor… curious if you ever solved the problem. My next step was going to check for continuity from the seat sensor wires to the terminals on the Main Ecu, assuming maybe the wires broke somewhere or a mouse chewed them possibly.


Any help is very much appreciated.

Save yourself a lot of time and frustration, engage the PTO while sitting in the seat. If the engine continues to run, your seat switch is alright.
Now, on the lower RH side of the dash tower is a Hydrostat pedal safety switch which is adjustable by loosening the jam nut and screw the switch down a turn or two.