Txt erratic throttle and voltage drops

[Loweredf1]

I have a 2008 ezgo txt series 36v cart that has developed a problem. The cart started randomly loosing power then coming right back. The problem seemed to get worse at battery voltage went down. We kept dealing with it to the point the cart would sometimes completely shut down for random amounts of time usually less than a minute then take back off again it even left us stranded a few times but would take off after setting a bit.

I replaced the throttle pickup sensor at the pedal and put a 400 solenoid and voltage gauge on the cart. This didn’t fix anything but I was able to keep a eye on voltage during the power cut outs. The voltage will randomly drop sometimes down to 19 bolts and I can hear the solenoid click in and out when voltage gets that low. On the advice of Scotty b at carts unlimited I replaced the controller with a alltrax sr 500 and put a new HD F&R switch on. We though the cart might have been overheating the controller as I use it to pull my drag car occasionally and might have hurt the controller. I put the new parts on this week and am still dealing with the same issue as before. Cart would drop voltage and surge with no load just driving around on flat ground. I talked to Scotty again and we was thinking possibly a battery or two may have a short that jarring around while driving is causing voltage drops so I had my wife drive today with no seat while I watched put a volt meter to each battery. Well now it continued to surge sometimes to nearly a stall but usually just a second or two of surge but the battery pack held 37v during the surge but would drop to around 33-34 for a flash when power came back and it takes off and I never found a battery that showed any huge drips like we expected.

I have load tested the battery’s and they all tested good but the battery’s are around 4 years old.

All battery and motor connections are clean and tight. I’m at a loss. I’m leaning toward battery’s but nobody wants to replace battery’s before there due Anyone have something I should check out?

[Loweredf1]

I have been testing the its system today. The only issue I see Is base voltage with throttle pushed just far enough to click in solenoid Is 7.3 volts which is lower than it should be. Full throttle I see 5.3 so im in range on that one. I left the meter on it while driving and signal held steady when the cart was surging. Pack voltage is still holding 37+ when the cart surges but drops to 32 as the cart excell back to speed. Sometimes immediately surging again sometimes waiting 15-30 seconds before surges again. Tested each pack again with my load tested and all battery’s are staying within range 5.9-6v under load.

[Loweredf1]

Well since I didn’t get any suggestions I will tell the diagnosis. After $700 I’m new parts I was going over wiring last night and started seeing a voltage drop while setting. I ran though the wiring page from the alltrax controller figuring out all the systems and found I had 38v at the charger port but only 18-22v at the MS on the F&R switch. There is a connector on the smaller wire coming back from the charge port that feeds the MS and on to key switch and down the line. The connector was loosing contact inside. Cut it out and put a heat shrink but connector in its place and the cart is running great. The one connector I overlooked bite me in the ***. Hope this helps someone down the line.

[Dixie Chopper]

Sorry you didn't get any help. Good to hear you got it fixed though. It's possible the experts might have missed your post because someone usually responds.