90 marathon won't move forward or reverse

[grandpa1]

good afternoon buggies gone wild. I have a 1990 EZ GO marathon 36 volt car with controller cart will not go forward or reverse but solenoid clicks. does anyone know where I can find a troubleshooting guide for this cart I have looked on the web and found a few things but not exactly what I need. Any ideas would be wonderful. Cart total voltage is 37.1

[grandpa1]

I'm open to any trouble shooting help because I can't figure this one out.

[JohnnieB]

Originally Posted by grandpa1

good afternoon buggies gone wild. I have a 1990 EZ GO marathon 36 volt car with controller cart will not go forward or reverse but solenoid clicks. does anyone know where I can find a troubleshooting guide for this cart I have looked on the web and found a few things but not exactly what I need. Any ideas would be wonderful. Cart total voltage is 37.1

They all work about the same, so something close ought to be suffice for generic troubleshooting.

If the solenoid clicks in both F and R, but cart does not move in either direction, the problem is in the high current circuit.

The attached schematic is a typical Marathon controller cart with a Pot-Box throttle. The High current circuit is highlighted. There is a single path from the main positive terminal on the battery pack though the solenoid, F/R switch and motor back to the main negative of the battery pack. If there is an open anywhere in that path, the cart doesn't move.

Connect a DVM between the B- and M- terminals on the controller.
When the pedal is pushed just far enough for solenoid to click, you should have FULL battery pack voltage.

If you don't, trace the circuit towards the Positive side of the battery and when yopu find the voltage, you just passed over the problem.


If you do have FULL pack voltage between B- and M-, push the pedal to floor and voltage ought to decrease to Zero. If not, either controller or throttle input to controller is bad.

[grandpa1]

I will be on this first thing in the morning. Thank you for replying.

[grandpa1]

OK here is where I am at so far. Every cable going to the motor is compromised . melted looking and old and one cable is actually bare from laying on the motor. So I gotta fix all that first plus one stud broke when trying to get cables off so I gotta pull the motor also.

[JohnnieB]

Sounds like replacing all 13 cables with 4Ga welding cable and rebuilding motor is needed.

It depends on which motor stud broke, but studs come with some brush kits.

[grandpa1]

Motor was junk. The armature was coming apart from high heat it appears. Put in another used one and fixed the cables and she runs fine now. Thank you again for the support.

[JohnnieB]

Heat will do that.

Glad to hear you got it going.
Thanks for the feedback.