Sorry I didn't say that well. It is a manual turn to left or right. I have worked on many walkie stackers but I have never had one like this one where the handle when pulled down seems to be locked into place. It moves about a 1/4" inch in both directions and that is it.
Update: I believe water got in on the bearing. I pulled handle hard to the left and right and it broke loose probably some rust and has worked ever since. I use it around the shop everyday just to make sure it is fixed.

There are a few on the market with either power assisted manual tiller arm steering OR full power steering from the tiller.

I doubt it don't know of any Walkie stackers with a electric motor for turning the handle/ drive unit to the left/right.....it's all arm strength....

It is a walkie stacker.
It really feels like it is locked into place.
The battery was totally dead on this unit.
I recharged and it is holding a charge well.
Could it be electronic problem?

Guess I need clarification.....is this a Walkie/stacker walk behind pallet truck or a standup reach truck.....a Walkie stacker is a manual steer where you moving the handle to the left/right rotates the drive unit on a large support bearing,a reach truck has a drive motor that is electric USIALLY that moves the bearing/ drive unit left and right.

Anything from a water bottle to driver's gloves, debris, will lock steering

Thanks Kevin I will check out, but it feels like a lock out in a sense. Hard to explain but I am trying to find a pdf manual for the unit. Thanks again.

Sounds like the large bearing that attaches to the frame that supports the drive motor and drive unit is frozen,probably hasn't been greased in a while??? There should be grease fittings either on top or underneath but is more than likely seized up and needs replace.