New Holland 2120 tractor, will not go forward or backwards

[MoochieHTM]

Have installed new module switch on lever and have voltage to the solenoids...thanks for any ideas or suggestions.

 

[jmc]

Long shot, but my 1920 of the series did this as I was bush-hogging. Turns out some brush had disconnected a plastic wiring harness connector under the tractor.

 

[Lowrider2120]

Must be a common problem. My 95 2120 Mode Command HSS with 4K hours will happily go into neutral and forward but will not properly go into reverse. It will click the valve in reverse but will not handle power or go backwards with any power and eventually stop moving in reverse. We checked power to the control module and it is getting 12 volts and there is voltage to the solenoid...not sure it is fully engaging the valve (spool) to allow rearward movement. 1st guess is the solenoid but my fingers and toes got cold before we could pull it out and check operation. What is it likely to be causing the problem? My manual does not show the mode command system and can't find an online trouble shooting procedure.

 

[metalmole]

Haven't worked on a 2120, but other equipment with electrical shift valves....Make sure the valves are getting a good ground, seen some bad grounds cause problems...

 

[Lowrider2120]

Thanks Metal!

There are 2 grounds on the transmission case adjacent to the control module and we cleaned then and it seemed to help but not significantly...didn't fix the problem.

 

[metalmole]

Also check your voltage with a good digital meter, could have some bad wiring that only has a strand or two making connection, try checking voltage with the valves energized, that will show if voltage is breaking down under load...

 

[Lowrider2120]

That's a good point. We'll do it...tractor is 50 miles away but get it done. Thanks!!

 

[metalmole]

One other thing is on most of the machines I have worked on the trans control valve has ports to install a gauge to check pump pressure as well as ford/reverse pressures, u might look for these if your trans has them...my YM1510 does not have them...

 

[Lowrider2120]

I think I remember seeing that in the manual. I'll check...Thanks!!

 

[metalmole]

Any progress on your problem ??