Hunting Buggy Build. Help appreciated!!!

[onewheelcop]

When you put it in forward or reverse the solenoid just clicks and doesn’t move. But if you mash the Excelerator all the way to the floor after the solenoid clicks my voltmeter goes all the way down to 37 V but it’s not moving and nothing appears to get hot even if your keep your foot on the Excelerator. I had this issue for 30 to 40 minutes with it not wanting to go. Finally it clicked and started going forward but it seemed like it only had half the power that it did before. Now it seems to go in forward and reverse yet it’s a very delayed response. Before when you put it in forward At the Touch of the Excelerator pedal it had approximately 90% of its torque at the crack of the throttle. Now when you mash the Excelerator pedal all the way to the floor there is a bout a half a second delay before it ever starts moving forward with limited power.
I’m thinking that due to my voltmeter only showing 37v at WOT, that the Solenoid isn’t letting the current through to the motor??? Could my stock motor be going out???? Is it common for the motor to shut off and on when it’s going out??
Please help I’m at a loss

[onewheelcop]

https://www.youtube.com/watch?v=3NZgGIIhvHY

[onewheelcop]

https://www.youtube.com/watch?v=VjIZpqdcgv8

[BBBHC]

Well I'm certainly not a guru with all this. If I had to guess, I would say that when you were on the steep incline, the motor needed more amps than what the controller is either programmed to deliver/or could deliver safely. So it shut down, to prevent damage...

Wait for one of our resident gurus to give better/more insight on that.

If you can hook up your lap top in the same scenario, and save a monitor file to post in this thread, that should give the gurus here the information you need to start trouble shooting.

[onewheelcop]

Originally Posted by BBBHC

Well I'm certainly not a guru with all this. If I had to guess, I would say that when you were on the steep incline, the motor needed more amps than what the controller is either programmed to deliver/or could deliver safely. So it shut down, to prevent damage...

Wait for one of our resident gurus to give better/more insight on that.

If you can hook up your lap top in the same scenario, and save a monitor file to post in this thread, that should give the gurus here the information you need to start trouble shooting.

I would agree with that theory, except for the fact that I have a Brand new SR48600amp alltrax controller on a bone stock 2hp motor... I was leaning more on the lines of the motor going out but im not sure if my carts symptoms line up with that theory. The biggest thing that has me puzzled is the fact that when the Solenoid clicks and the cart doesn't move, upon full throttle the voltmeter shows 37v. That means that when the peddle is pressed, 14v's of Power are pulled from the battery and are going somewhere? Nothing seems to be getting hot!!

[JohnnieB]

Dropping about 14V and nothing getting hot, points to one or more batteries in the 48V pack failing under load.

Check the individual battery voltages while under load. They should all read nearly the same voltage with no more than about 0.1V difference between highest and lowest.

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Another possibility is a high resistance area in the high current circuit that is hidden, so the heat is not readily apparent. A place like the contacts in the F/R switch.

A stock EZGO F/R switch is marginal for a stock (275A) controller, so it doesn't stand a chance with a 600A controller even when feeding a stock series motor.

When it goes, if it hasn't already, install a super-duty F/R from Carts Unlimited, or a super-duty reversing contactor.


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If the batteries test okay, connect your DVM between the B- and M- terminals on the SR controller.

Lift rear tires off ground and put on jackstands.
Either have someone push pedal just far enough to make solenoid click or jumper B+ to solenoid's small terminal with two red wires on it.
Voltage between B- and M- ought to be exactly the same as the voltage between the 48V battery pack's main negative and main positive terminals.
If it isn't go looking for the missing voltage with the red test lead.

[onewheelcop]

Originally Posted by JohnnieB

Dropping about 14V and nothing getting hot, points to one or more batteries in the 48V pack failing under load.

Check the individual battery voltages while under load. They should all read nearly the same voltage with no more than about 0.1V difference between highest and lowest.

--------------
Another possibility is a high resistance area in the high current circuit that is hidden, so the heat is not readily apparent. A place like the contacts in the F/R switch.

A stock EZGO F/R switch is marginal for a stock (275A) controller, so it doesn't stand a chance with a 600A controller even when feeding a stock series
When it goes, if it hasn't already, install a super-duty F/R from Carts Unlimited, or a super-duty reversing contactor.


----------
If the batteries test okay, connect your DVM between the B- and M- terminals on the SR controller.

Lift rear tires off ground and put on jackstands.
Either have someone push pedal just far enough to make solenoid click or jumper B+ to solenoid's small terminal with two red wires on it.
Voltage between B- and M- ought to be exactly the same as the voltage between the 48V battery pack's main negative and main positive terminals.
If it isn't go looking for the missing voltage with the red test lead.

Thanks Johnnieb, I just got home and the pack is charged to 51v. I took it for a spin and everything did alright until I torture tested it on that same hill. It would spin for just a second the stop. All power gone. I did notice that under heavy load the volt meter never fell below 45v. But once it lost power it dropped instantly to 37v. I kept pumping the accelerator quickly, probably 10 times and then it started engaging again. Put it under a load and it did it again. Same thing. Patted the pedal multiple times until it started going. The very bottom (A) post on the F&R switch is a little warm as well as that same wire where it connects to the motor. It seems to do fine until I really call on it, then it’s lights out. Does the controller have a light with flashing codes?

[JohnnieB]

LED is next to the USB port. Attached are the error codes and definitions.

The errors also appear on the monitor screen in Toolkit and in the data log if you record one.

[jclark138]

Since I know zip about batteries, Amp hours, range, etc. I’ve found this thread pretty informative. I can wire a house, but a golf cart? not likely.
JohnnyB - as always, you da man. Thanks to all y’all.

[onewheelcop]

Just wondering if my symptoms are Motor related. The only things i haven't replaced with brand new parts are the Motor,F&R Switch, and the Pedal micro switch. So really just not sure what it could be. I cant seem to get it to repeat its issues. Ran fine yesterday, so this has got me scratching my head. Now I'm afraid to us it outside of sight distance from my house.