to john deere 2010 ive got a 2020 john deere gas it did the same thing. when it would act up for example when we would be plowing with the plows down it acted like hyr.went out no steering/brakes/3point hitch none of them would work.but if you turned the front wheels all the way to the right and rev the motor everything would start working ok.but this only happen every now and then.it took a long time to find problem.under the battery box kind of out of sight iam not sureof proper name but there is a hyr. vale when you take it apart change o-rings inside mine had a bad oring but changed all of them it fixed it it never acted up agian. dont feel bad it took me a very long time to find the problem also. hope this helps you .this value contolls steering/brakes/3 point lift when the o rings go bad it lets its bypass causing the problem