Considering the price of hiring someone to troubleshoot your golf cart’s motor controller, it is far cheaper for you to do the repair work on your own. Fortunately, replacing the motor controller on a golf cart is fairly straightforward. It’s a question of removing the entire motor controller and replacing it as one unit. Unfortunately, a motor control unit is fairly expensive. There are a few things you can try before resorting to completely replacing your motor controller.
Remove the engine cover and disconnect the battery.
View the wires leading to motor control unit. If the wires are corroded, scrub with a wire brush or replace.
Replace the solenoid. It should be held on with a few bolts and possibly a metal bracket held on by a screw. There will be at least two wires on the back of the solenoid; they must be removed and inspected and replaced, if necessary.
Reconnect the battery and test. If there was a faulty solenoid or corroded wire causing the problem, the motor control should work.