ATV: Yardsport YS36 4x2 The motor is not working

[zerocoolorez]

Hello Buggies gone wild forum ,
I hope this Thread is in the correct place as.
Personal Story ahead : I got High functioning Asperger syndrome.
The vehicle was purchased on an auction and a relays seems missing.

I received a Yardsport Electric YS36 from an auction and now I am left to troubleshoot the unit.

I worked on this unit for 48 Hours straight now and I am unable to get the motor to run.

EVERYTHING including break light is working but it does not MOVE.

This is what I have done so far.:

I checked the SHUNT Motor by itself and its running properly when hooked up to the battery using the required circuit.. ( F1 F2 A1 A2 )
I checked a visible relays close to the batteries ( JD1912 ) using a 12 Volt Battery and my Fluke Multimeter and it is OK.
The preowner bought new Batteries ( Refurbished ) and I checked them with a nice charger
The Batteries are in gooood condition.

I love electronics a lot but there are 2 things that I cannot properly Identify. (The control unit pinouts and the copper thing in the pictures)
And one last thing : It seems like there is a relays missing in the Front of the Vehicle. The socket for the Relais has the same dimensions as the JD1912 Relais in the back of the vehicle. ( I made a copy of the JD1912 40 AMP relays using another Relays that I had laying around 35 AMPS ) but the vehicle is still not moving. SO I assume the pinout is different or it maybe a "normally closed" ( I tried that with my relais and it did not work so maybe the wiring is different )

I have absolutely no knowledge of the "controller BOX" or how to test it. What I am able to do is open it up and do some rework on it or replace a chipset ...

I traced the Throttle "switch" and it is functioning properly ( the more I press the Gas the more the OHMS change )
Also I traced the GAS Paddle ( close to the throttle switch ) and there was another switch ( on off ) that is closed whenever the Throttle is pressed in any way.I am unable to find schematics on the Web about this controller unit , but was able to trace some of the wires ( like throttle and the mini switch when the "Gas Pedal " is pressed.
The Forward and reverse switch is working and i traced them to the control unit pins.

On the control unit there is a gray wire that is pulled out its on the same string of wires as the Throttle ( OHM changer ) and the switch that is closed when you press the "Gas" Pedal. (Its definately not the throttle but the other switch ! )

I will now post a lot of pictures and I am hoping that you could help me narrow down the problem. Sorry if the pics are overkill.

I was not able to find a DIODE that may have been burned due to the reverse voltage. ( Maybe on the inside of the controller unit ? )
Could someone please tell me the workings of the control unit on how I can check it ? A PINOUT would really help me. Maybe someone could take a look at his ATV and tell me what he things are the PINS. There is another component that I was not able to identify but it seems like its a COPPER looking Relays with 2 BIG Red wires going to it and on top there is 2 tiny wires. Ill post that picture.
Please let me know what info may be missing..
Oh ! And please see the picture of the 2 wires in my hand. One of them goes to the relays in the back and the other end I dont know where it should go. And another gray wire where I dont know where to hook it up to.

The person that is helping me to make the step to fix it will get 100 Dollars using Paypal for your time.

Please message me your thoughts and maybe a Video conversation using Facebook messenger would be nice to narrow down the issue?

Thank you

[Fairtax4me]

Looking a that setup its a far more simple layout than most golf carts, so should be pretty easy to narrow down the problem. Which is likely to be the controller.

That "copper" looking thing is the main solenoid. That sends battery power to the motor, and the controller motor power circuits when activated. If the controller is working properly it should provide 36V to one of the small pins, and ground to the other small pin to close the solenoid contact inside. That should then deliver 36V across the large posts to the controller and motor. You should be able to hear and feel the solenoid click if all other inputs to the controller are working.

There is a pre-charge resistor and also possibly a suppression diode in the small red wire assembly that goes to the two large posts. That is to supply the controller capacitors with 36V and supply minimal power for the throttle control, and other inputs to the controller. The diode is to provide voltage fly-back protection when the solenoid opens.
If the resistor is not burned out you should have battery voltage on both sides of the solenoid, and present at the B+ terminal on the controller.

You can remove the resistor wire, and check that the solenoid is operating by supplying 36v and ground to the small pins, listen and feel for it to click, and check that 36v is present on both posts when the solenoid is closed. Remove power from the small pins and see that the solenoid opens and you should have power on only the large post that the battery supply cable is attached.

Assuming the solenoid checks out, It seems like you've tested every other component the only thing left is the controller.
There may be some testing that can be done for the controller to determine if it's working or not, but I'm not familiar enough with those to say.
I did google the model number on that controller and it does look like that's a difficult to find controller used only in smaller or foreign markets and it's not exactly a reliable part.
You may be able to get in touch with FSIP and see if they have a conversion kit available to install a Curtis controller that should be much more reliable.

Another option might be to install an Alltrax which you may have to wire everything yourself, but you will have programming ability and more options for possible future power upgrades.

[Mathcky]

Did you ever figure out the problem?