2006 G22E (48v) Battery Drain and Not moving

[Mnjfoe]

Hey all, First let me say I know nothing about golf carts. We bought a used 2006 Yamaha G22E (48v) for my mother who has MS. She can barely walk even with her crutches/walker, but this would allow her some freedom to get around her development. (The POS We bought it from knew all this but still took our money without telling us there were issues,but that’s for another post.) I just want to get this working for her but no one around here will work on Yamaha for some reason.
So, the batteries show fully charged but only 20v showing, when I switch from tow to run the voltage drops. I changed the selonoid but nothing changed. It worked for about a week when we first got it then just stopped dead and never moved again. The batteries all seem to charge well when I can charge it,but it won’t take a charge until it’s at 40v (so I’m told). I know I’m all over the place here. I just really need some guidance please. I’m so frustrated , I just want to get this working right for her so I know it won’t break down. Everyone else in her development has working carts and she is trapped in the house already as it is with the MS and now Covid. Any help would be appreciated . Thank You Kindly, Mike

[Croqezgo]

I am sorry to hear about this POS seller. In all honesty, I bet the batteries are dead. Sometimes you can revive them for a small amount of time but still... they die shortly thereafter. What year are the batteries? Have you checked the water in them? It likely does not matter, if they are low, permanent damage has been done. I have had luck buying reconditioned/used batteries that are reputable and tested. But beware, these are only a small savings for a small amount of time as well. If she is not going far and you are willing to maintain them. However, you probably need new batteries. Test them as a pack after full charge. Not with a battery meter, but an actual multi-meter.

[Mnjfoe]

Thanks for the reply . I checked the water in all the batteries and all was good. The batteries are all 2018. Ill check their voltage on Sat again when I get there. Again, I have Zero experience with carts. Should I disconnect all the batteries and Che k them all individually ? And I know they’re dead right now, but I do have an old rolling charger. Is there a low number I should be on the look for, meaning If all but 2 batteries are good but 2 are showing very low voltage. Is there a number that batteries can’t be recharged from? Does that make sense?
One last question, how do I test the controller?
Thank you for taking your time to help and reply. It’s very appreciated. I don’t know who else or where else to ask for help.

[Mnjfoe]

I also found this wire not attached to anything, but it looks like whatever it is was bypassed? Is there a way for me to just get an entire new wire harness so that it’s all hooked up correctly? I’m sorry for all the random questions. But no one around here will even come look at it for me because it’s a Yamaha. So I’m on my own and might as well be working in a satellite box I have zero knowledge of any of this

[Croqezgo]

That plug does not matter that I am aware of. Batteries should all have over 8 volts at full charge to even be in the ballpark. Then the question is, are they really good? I had some similar situation and the batteries were the culprit twice.

[cgtech]

That loose plug is a diagnostic port.

[Mnjfoe]

I bought a multimeter to check the batteries, again this is way out of my zone so I’m learning on the go. Is there a range a good battery would be when fully charged vs needed to be charged and also is there a reading that would tell me that a battery is just dead and won’t even be able to be charged? I did look into buying new batteries but had no idea the cost ! I just don’t have that kind of money available to me. So if there is a battery or 2 that are dead and need to be replaced is it on to just replace one or two? I read somewhere you should replace all at the same time but does that really matter or is that sales talk? I can’t afford to buy a whole set.
Again I really want to Thank everyone for their help and putting up with my possibly ridiculous questions , it really is appreciated. I know to some it’s just a golf cart but for her (my mother) this really is the difference between being stuck in a house and having some sort of freedom to get outside. I still can’t believe there are people out there that would knowingly rip someone off like that knowing their condition and reasons for wanting to buy it. But for now I REALLY just want to get it moving for her.
Any other ideas on what to check, test or look for?
**it seems at though the selonoid isn’t clicking on either now. I just installed a new one but it doesn’t seem to be charging. Would/Could that also be caused by bad batteries ?
Thank You All!! Sorry I’m scattered all over here