I have a John Deere 700h that is stuck at 1.5mph in foward and reverse. It won’t allow me to adjust speed up or down. No codes are displayed and fuses are good.
Please post the machine's serial number. Did you remove the cover from the TCU and scroll to codes to see if any are in there?
T0700HX943161 I have not checked that yet
Does your machine have the speed in grip (buttons to change speed), or do you have the speed control lever?
It has the buttons to change the speed
While you have the cover off the TCU, press MENU until DIAG is in the window, press select. Press NEXT until SPd-mV is in the window. Post the reading without touching the button, with the button in the up position, and the button in the down position.
Also have codes F3T0, F3T1,F353,F393,F3H4 and F330
Did you monitor the speed switch voltage as outlined above in post #6? When you scroll through the codes and the word "end" appears, press and hold select until "F300" appears. That means the codes are cleared. Run the unit and let's see what comes back. I bet the F3T0 and F3T1 comes back. Those codes are for the transmission speed switch.
I will try that right now. Thanks a ton for all the helpful information.
F3T1 is the only one that came back
F3T1 - (2.15 mph)(Service Code) Speed In Grip (B4) This service code indicates that the Transmission Speed Control Switch voltage is between 0.27 and 0.50 volts. Check your messages.