2005 club Car DS IQ electrical problems

[indawoods]

We inherited an 05 Club car DS IQ and even though it's almost 10 years old it's only been gently used for about one year just for golf. It's stock except for the batteries, 10" wheels, a new paint job and I believe it got a new obc around 2007.
Last Wednesday I used it for golf and on the 3 mile return home it felt a little sluggish. I checked the batteries and they were reading 49.5 which didn't seem too bad for 18 holes and 6 miles on the road. Friday I played golf again and during just the 4th hole it went from acting normally to almost dead between 2 shots. I was on level grass and it felt like I was trying to climb Mt. Everest. I let it rest a moment and tried again. It started to move slowly and then there was a loud pop that sounded like a backfire. Since we're talking about an electric cart I figured it was some kind of electrical arcing. I tried it again and it was moving slowly but I was able to get it off to the side and after one more "backfire" I left it until after the round. I went back and was able to get it home though it felt sluggish like it had 2 days earlier. I checked the batteries again and they read 50.3 and each individual battery was at 8.4. I checked all the major wire connections and they seemed good and I also inspected for anything that looked fried and found nothing. Attached are some pictures of the motor / controller compartment.
Doe anyone have any thoughts on this strange behavior? Thanks for any help, I really appreciate it!

[jakesnake27]

How old are the batteries? Also, the cart does have a controller cover right?
If the IQ controllers even look at water, they crap out, they are very sensitive...

[indawoods]

The batteries are 4 years old but seem to be holding a good charge and haven't given me any indication of failure. Yes, the controller cover has always been on. I just took it off to see if anything looked fried.

[indawoods]

Jakesnake, After rethinking your question about the age of my batteries I did a little experiment. I swapped a set of 2 year old trojans from my older 1999 club car (series) and put the 4 year olds in that cart. Voila! The older cart began to give me the dead battery death rattle that I've experienced several times before in that older cart. I guess the newer carts don't give a warning "shake" over a period of time like the older series carts do to let you know it's time for a new set. I gave the 05 cart with the trojans a test drive and all is good. Whatever caused the loud popping (backfire) sounds apparently wasn't terminal! So it's new batteries now for the older cart which I prefer to drive anyway (It's faster!) and the newer 05 (for my wife) will be happy too with the 2 year trojans. Thanks very much for your quick response and your help!

[jakesnake27]

Originally Posted by indawoods

Jakesnake, After rethinking your question about the age of my batteries I did a little experiment. I swapped a set of 2 year old trojans from my older 1999 club car (series) and put the 4 year olds in that cart. Voila! The older cart began to give me the dead battery death rattle that I've experienced several times before in that older cart. I guess the newer carts don't give a warning "shake" over a period of time like the older series carts do to let you know it's time for a new set. I gave the 05 cart with the trojans a test drive and all is good. Whatever caused the loud popping (backfire) sounds apparently wasn't terminal! So it's new batteries now for the older cart which I prefer to drive anyway (It's faster!) and the newer 05 (for my wife) will be happy too with the 2 year trojans. Thanks very much for your quick response and your help!

Awesome!

It's actually the drive system that causes the shake. A series will shudder when it experiences low voltage. A sepex (IQ is what CC calls it) will just lose power and slow way down.