I'm kind of doubting it.

You didn't mention if it has a Curtis controller or EV10
The Curtis's are easy to diagnose.
The pot wires are the 2 lower spade conectors.
The top spade conector is a bat. positive (switched at brake switch)
The pot wires should start @ >5Kohms and go down to <100 ohms for hi-speed
To eliminate the pot and pot wires, jack the drive wheel off the ground, put the unit into either travel direction and short the 2 lower spade contctors on the pmc controller together. if the unit starts driving then it's a pot or pot wire.
PMC controlers are peculiar in that if there is hi resistance in the drive motor circuit, it won't push higher current until the resistance goes down.
(it monitors the voltage drop instead of the actual current)
Things like drive motor brushes and worn contacts will create no travel, without the usual sparking. The controller just puts a voltage accross the motor and waits for somthing to happen.

So, in point form:
1) make sure there is a battery positive and negative at the appropriate studs (the top 2)

2) make sure that you get a bat. pos. at the top spade connector

3) check resistance on the pot wires (or jack op the unit and short the 2 pmc spades after closing a direction contact with the dir. controls)

4) check voltage drop across the PMC controller.
You measure from the battery neg to the M- post (the one on the side next to the spade connectors)
(If the voltage stays high the PMC isn't trying to do anything)

5) check voltage drop across the motor
measure across the armature under load, and across the fields under load (under load= while trying to travel)
Hi volts across the armature will likely be brushes
Hi volts across the fields = cooked motor

A high voltage indicates an open.
6)Check voltage drop across the contacts and cables.
again hi = a problem

7) perform the patented Mike Norris PMC short test.
With the drive wheel off the ground, take a screwdriver and connect the batt neg and the m- together. Then close a direction conact.
If unit jumps (and has passed all the other tests) it's a bad PMC controller
If the unit does not jump then its a motor, or cable or contactor. Do some more digging.

There are a couple other failures that are possible within the PMC controller, but you should here a hum from the controller when trying to travel.


If it's the EV10 then it get's a little more complicated, but start at the pot wire (measure volts from the card to batt neg. should start @ ~5V and drop to ~0 at wot)
An open motor, contacts or cables will do the same symptoms.
Unfortunatley, so will a ton of other wiring problems, up to a failed card...

Let me know if it's an EV10 and i'll try to help you through it...