2004 Yamaha G22E Not Moving, Solenoid Clicks, Batteries OK, Tested Motor, What else?

[Bradlpops]

Hey fellow carters, I will apologise in advance for the long winded post but I am a bit stuck and this is the first electric cart I have delt with, i do prefer petrol / gas carts personally because im more mechanically minded rather than dealing with electrics.. Anyways..
I recently picked up a 2004 Yamaha G22E 48v electric cart from an auction a week ago and I cannot for the life of me figure out what is wrong with it.
When I picked it up I put it into forward, it shudderd and crawled and then took off and drove fine at speed, as soon as I went to load it onto the trailer it did not want to know about it and stopped, I reversed back in a shudder again and tried a run up but it still would not climb the ramps onto the low trailer. Anyways after getting it back home and unloading it I drove it around my place, got plenty of room, still shuddered and shook a bit until it got up to speed in both forward and reverse and it was fine on the flat. Then I tried to drive it into my shed, a small 60mm (or 2.5 inch) jump onto the concrete, again it wouldnt climb it and when it was shuddering trying to get up the small lip and my foot flat to the floor it just cut out and died with a slight burning smell. So I pushed it into the shed and have had no responce from it since.
I charged the batteries up overnight, the whole bank held 51.4v, let it sit for a day off charge and came back and bank read 51.1v but still no go from the cart. Solenoid clicks when key is turned on, clicks again when pedal pressed (but clicks again when pedal stays pressed for a second or so, it does vairy) and clicks when pedal is released, it also clicks when in run and you move the cart backwards or forwards (guessing this is a breaking feature) tested resistance on the solenoid as best I could, it read 0 ohms after being disconnected, seems ok to me but unsure. I did notice that when I tested the plug that goes to the small wires on the botom of the Solenoid i get about 18v when i press the pedal for a short while then it disappears. Then I release the go pedal and the voltage fluctuates between 18 to 26v then stops.
So I put my car on the hoist and lifted it up off the ground a little and disconnected the motor and connected the A1 to F1 terminals together and A2 to F2 together with jumper cables and connected a 12v battery to the motor (positive to A1/F1 combo and negative to A2/F2 combo) and the motor ran fine (I only did this for a brief moment each time) I then swapped F1 and F2 terminals and it ran in reverse just fine also, so its not the motor.
So next thing i did was remove the batteries that the cart came with and put in 4 12v ones that i had in my shed that i know are good to get my 48V, banked together i got 51v but still had the same responces, solenoid clicks, revese beeper comes on when R is selected, press the go pedal, solenod clicks again but still no wheel spin.
I took the original 8 volt batteries into town and had them load tested at 2 different shops and they are stuffed, so they will need replacing.
I have inspected the wiring underneath the cart after lifting it all the way up, quickly tested the gas and break switches altho im unsure what the readings should be for these switches, I did notice one wire had been cut and rejoined with blade crimps from the accelerator pedal but other than that the rest seems fine considering it ran before I got it to my shed.
So my last guess is the grey controller box thing next to the solenoid. What are your thoughts? and is there a way i can bypass it just to test if that is the fault?
Before I spend anymore money (if its worth it at this stage) I would like to be sure of what I need to replace aside from the original 8v batteries ($1062 is the cheapest I can find in Australia WITHOUT freight for 8v 160AH batteries) and controllers online are between $700 and $1200 AUD from what i have found new. Hoping someone will "loan" me a part to try before purchacing a new one.
I live over 300km out of Perth in Western Australia and parts are a little hard to come by locally.
Thanks in advance, any help is appreciated and i can post pics and videos of the testing i have done and am willing to try what is recommended that i have not tried so far.

[rsnelly]

I had the same jerky motion with my 2003 G22. I replaced most of the switches, no change. I decided it was the controller or Motor. So I replaced both with upgraded versions (400 amp controller and faster motor). Now runs great, smooth and fast.

[ojo]

I did the Same with a not running G29, checked the motor and purchased a new Alltrax controller ( the Yamaha OEM controller are known for issues ). With realtime data of the Alltrax i've found finally a missing speed sensor and TPS sensor signal. Really worth the 350$...