1995 EZGO Medalist DCS 36v with Alltrax XCT500 stopped working

[SpeedbumpDC]

I have '95 EZGO Medalist DCS 36v where stock controller (was failing) replaced with the XCT500 / 400a solenoid combo from Scottyb. Super helpful with suggestions and quick shipping. Install went fine and I upgraded battery and motor cables to 2g as well.

I wasn't quite getting the expected performance (16mph on flat but would drop to 8mph on hills - stock 18in tires, 1 year old Interstate 6v batteries) and was taking monitor files from the XCT to troubleshoot.

My son drove it up a hill the other day and it quit in the middle. Got it home but have not been able to get it to work since. Here's what I am seeing:

Battery bank showing 38.6v
Controller turns on when cart on and switched to forward - solid green indicator
Controller solid beep in reverse as expected - again solid green indicator
When pedal depressed in forward, I hear the solenoid click - controller light turns solid red when 100% throttle is reached - no cart movement
When pedal depressed in reverse, I hear the solenoid click - controller light turns blinking red when 100% throttle is reached - no cart movement
Voltage on the main solenoid terminals is 38.6v on battery side and 37.9v on controller side until throttle is depressed and solenoid clicks and controller side voltage increases to 38.6v.

The cart ran for a couple of weeks after controller and solenoid upgrade so I believe I had it wired up properly per the diagram - though there was some performance concern as stated earlier.

If anyone has some suggestions, I'd welcome your expertise on where to start digging. Wondering if my son did something he isn't telling me about or if I made a mistake somewhere in the install.

[SpeedbumpDC]

Just to update and close this out, it turned out to be the motor.

I did the manual jumper cable test with a spare 12v battery and got no movement or response at all from the motor.
I decided to remove and tear it down (didn't have much to lose) and found two of the wires going to the brushes had blackened ends and had disconnected from the two brushes completely.

I bought a replacement brush kit for $27 and got them installed (after cleaning up the motor internals and removing a lot of the build up inside). It probably hadn't been opened since 1995.

Reassembled and it is working again.