Random throttle problems

Hello everyone. Its been a long time since I've posted anything. I have a converted Townie that, up until now, has been awesome. I shared a couple of posts on it last year, if you do an author search. It has a bitchen wood case. It is a 48V Ebikekit, so 22A controller, combined with a 15Ah battery from Calibike. The motor is a geared rear hub drive from Ebikekite, similar to the MAC 10T.
The bike has been acting up lately. Sometimes, the motor activates on its own without any throttle input. Other times, the throttle won't activate the motor at all. Sometimes the motor won't cut off when the throttle is released. Its a very dangerous situation. I have the rear wheel suspended while trying to find the problem. I have another ebike, a folder, also with an Ebikekit. I have swapped out the throttle from this bike, no change in the problem. I ordered a new accessory cable from Ebikekit, and swapped it out. No change to the problem. Are there any ideas out there as to what the problem/solution could be, short of replacing the controller or motor?

It sounds like a throttle connector problem. Since it happens with two throttles, it must be at the controller. Carefully inspect the throttle connector on the controller and make sure none of the contacts have pushed back in the housing or got bent. If that looks OK, next I would open the controller and try to trace the throttle wires to the board and looks for a break or pinch.

Before opening the controller, try measuring resistance from the throttle ground wire (usually black) to the battery negative on the controller. This should be near zero ohms. In you case it sounds like this connection is loose. It's fair to wire it directly to the battery wire if it's messed up inside the controller.

You could also try measuring the throttle signal voltage. Put voltmeter negative probe to battery negative and measure the signal pin while advancing the throttle. Should go from a little less than 1v to around 4v.

I checked the pins, connections, and cracked open the controller. Everything checks out visually. I even swapped out the controller from my folder, and no change in behavior. I recall that I had problems with the folder's throttle too, although not as bad as with the townie. So I am ordering two new throttles from Ebikekit. I am not equipped to run voltage and resistance checks. I will go to harbor freight and pick up a multi tester if the new throttles fail. Thank you for your input, Fechter.