Forward/reverse not working - error #6

Newbie first post. I don’t know what terms to search for. I am trying to get a Lafayette NEV on the road. I purchased it in non-running condition. I thought I was good to go but the forward/reverse selector switch/circuit is not working. I can barely hear a relay clicking when I toggle the forward/reverse switch but I get an error message (-6) when I press the accelerator saying I did not select either forward or reverse. I cannot figure out what piece of equipment under the dash is supposed to give me forward/reverse. The NEV seems to be built like a GEM with a GE 72v 350amp controller, mfg. date 5-13-2002. There is a big, magnetically operated device with exposed copper contacts that snaps on whenever I turn the key on, GE CTTA 150AA 176XN. If I don’t select forward/reverse (since it doesn’t work) this device times out and the device snaps “off”. What is that thing called anyway, a contactor? I am wondering if that contator should be snapping one way or the other when I activate the selector switch on the dash… or, is the forward/reverse circuit within the controller, or?
My forward/reverse dash switch is a momentary on type that toggles between forward and reverse. There are indicator lights that should light up when I select a forward or reverse but the switch does not light up. I can hear the switch clicking as well as another relay clicking when I toggle it.