Nogo EZgo

[Yetti]

Hi ,
Have a 95 ezgo 36v medallion. Replaced all the batteries and controller,solenoid and ITS and forward reverse switch,and micro switches.
All are brand new ,battery pack reads 37.6. Key turned on ,solenoid clicks, but wheels don't turn. I put it up on jacks and tested the motor by disconnecting the leads,jumping a wire from s1 to a2 and hooking up 12v battery charger to the remaining leads.The drive wheel turned. I then also checked for continuity between terminals and had good continuity between the A1 and A2 also S1 S2, and none between the A's and s's.
Why wont this cart move.? All parts are less than a week old -batteries 5 weeks. The cart ran for a week after battery replacement, then died. I discovered a burned cable from F/R switch, replaced that too. Only way I can get wheels moving is by jumper wire test with battery charger.
Please help

[Sir Nuke]

seeing as how your solenoid clicks.....the problem is in the high current circuit (LARGE CABLES). seeing as how you stated that you had/found one burnt cables to the F&R and replaced that cable......most likely you have some burnt contacts within the F&R switch. before you take it totally apart, you could try to tighten the center post to see if you can reestablish continuity within the circuit.


oh and btw...... Welcome to our happy little corner of the net, and to BGW. There is a BIG fridge on the back porch with anything you can think of in it...help yourself...of course only take what you can LEGALLY have. Make yourself at home on one of the big fluffy couches, kick your shoes off, put your feet up on one of the tables, yes we are allowed to do that, mom's, dad's, wives', husband's, girlfriend's and boyfriend's here don't care....and take it easy.



oh...btw....every once in a while a food fight breaks out...so you may not want to wear nice clothes here.

Welcome!!

[Yetti]

Thanks for the welcome. Too bad I cant load my cart up and deliver more beverages.
As far as the F/R switch goes, I replaced that with a heavier duty model, and checked for voltage going to the s2 lead and it has 36.9 on both ends of the cable. So I am getting voltage to the motor. I took the leads off the motor check again for any grounding issues with ohm meter, also for continuity between posts, and then hooked it to the battery charger for the 3rd time. The motor turns the drive wheel when hooked to charger. I then hooked the charger to s2 cable and to cable end of the a1, and wheels turned. It will not turn when hooked up to the new components I installed.
I am thinking the temporary jumper I used to test s2 to a1 is completing the circuit because posts are kitty corner. What if I were to leave the jumper on and hook everything up normally? Would that fry my components?

[JohnnieB]

If you leave the jumper on and reconnect the cables as they are normally connected, you can burn out the Stator windings or take out the controller, maybe both.

What the F/R switch contacts do, is reverse the polarity of the S1 and S2 terminals on the motor so the current flows through the Stator windings in the opposite direction, causing the motor shaft to turn CCW instead of CW, or vice versa.

B- is connected to A1 on the motor via the controller (The control elements - MOSFETs - are located between B- and M- terminals on the controller)
B+ is connected to either S1 or S2 by the F/R switch contacts.

With A1 jumpered to S2 and the F/R is in one direction, the Armature will be bypassed, the motor will not spin and stall current will flow through the stator winding when the pedal is pushed. If allowed to flow for any significant length of time, the Stator will burn out.

With A1 jumpered to S2 and the F/R is in the other direction, B+ will be shorted to B- when pedal is pushed, taking out the controller.

Attach the jumper wires to a tree limb someplace and leave them there.
Troubleshoot the F/R contacts with Voltmeter or Ohmmeter.

[Yetti]

OK, I will go back and troubleshoot. Is 37 .6 V enough to spin the tires, as I read an older post of yours say it needs the full 38v charge? I have the cart on Jack stands.

[yurtle]

Should be good enough for troubleshooting, but I'd charge them before you call it a night.

[Yetti]

Well I have 0 ohms between all 4 contacts (same posts other side of f/r switch.) Again this f/r switch is brand new. I tried shifting it while holding down pedal to see if that made a difference , but no luck. The new controller is a 350 amp, with 3 blade posts M- B- and B+Solenoid. Since the old controller had a blade for A2, I removed the cable that went to the F/R switch as per instructions on the new 3 blade controller.

[yurtle]

Originally Posted by Yetti

Well I have 0 ohms between all 4 contacts (same posts other side of f/r switch.) Again this f/r switch is brand new. I tried shifting it while holding down pedal to see if that made a difference , but no luck. The new controller is a 350 amp, with 3 blade posts M- B- and B+Solenoid. Since the old controller had a blade for A2, I removed the cable that went to the F/R switch as per instructions on the new 3 blade controller.

I don't know if the Medallion is series, but when I went from a four blade series controller to a three blade controller, the cable still goes from where it originates before going to the forth blade, and continues from the forth blade to its destination. The cable merely goes directly from origin to destination, without taking a stop at the forth blade.

[yurtle]

Here's a diagram for my 3 blade controller. Mine has a cable from the FNR directly to the solenoid. Yours may be different, but you need to check your instructions and make sure it's wired correctly.

[Yetti]

Your diagram indicates 2 cables coming from the controller blade , 1 to the A2 terminal on motor, the other to the F/R switch. My old controller only had one cable that went to the F/R. ( no other cable). So I guess by bolting them together as the diagram states, it would be the same as my 1 terminal. I also noticed your diagram has a fuse in the POS wire near battery. Mine does not ,not that it makes a difference since I do have solenoid voltage. I am going to study your diagram further as this is a head scratcher for me...
I hope I can at least rule out the motor being bad since it always turned the wheels when hooked to my charger.