2003 Yamaha battery drain issue very odd, please help

[Gmrulz]

Hi guys, new to the forum. I've had my Yamaha for about 1.5 years and she's been a good one. I bought all new batteries when I bought the cart. It's an 8 volt system. So I noticed a few weeks ago the cart was very sluggish and would slow down very quickly. I tested the batteries with a voltmeter and the outboard batteries the one on the far left and the one on the far right were very low whereas the middle 4 had close to 9volts each still. I charged then tested levels were good for all 6 batteries drove it and the same thing happened got sluggish quick, tested again outboard batteries 5.x volts and center 4 batteries had 8.7volts avg.

So I don't get it, all the connections are good, all the batteries take a good charge but it seems like it's only running off the 2 outboard batteries. Any help?

[LPnTX]

How are your lights, accessories and radio hooked up?

[Gmrulz]

Originally Posted by LPnTX

How are your lights, accessories and radio hooked up?

No lights or accessories. Factory stock cart. Thanks for the quick reply.

[cgtech]

It sounds like those 2 are bad, coincidental. There is no possible way the cart is "running off those 2" batteries. A "series string" draws equally from each battery as it can provide (that's why one weak one can shut the game down). None are "picked or chosen from" for power, each must provide. Live in a freezing environment? Perhaps they were at the edges and froze? That would damage the outer batteries first.

[Gmrulz]

Originally Posted by cgtech

It sounds like those 2 are bad, coincidental. There is no possible way the cart is "running off those 2" batteries. A "series string" draws equally from each battery as it can provide (that's why one weak one can shut the game down). None are "picked or chosen from" for power, each must provide. Live in a freezing environment? Perhaps they were at the edges and froze? That would damage the outer batteries first.

Gotcha. This helps, being fairly new to electric carts I was unsure if there was something else controller wise or elsewhere that could cause this issue. I didn't think so but I figured someone else may have experienced this. So my plan is to charge all the batteries swap those 2 to the middle and drive it see if those same two I moved to the middle drop again and if so I know it's those batteries. I have done the same thing swapping coils on LS engines in GM cars and trucks to find the bad coil.

Thanks for the help!!!