EZGO 2017 RXV "freewheeling"

[Heem]

Folks,
I need your help solving a problem with my ’17 RXV.
Background: I’ve had this cart for about a year. The batteries are less than a year old and maintained. I’ve installed a new ignition switch, motor brake, solenoid, and charge gauge. All cables are new and corrosion-free. I’ve also added a street legal light kit. Power to the lights is provided through a 48 to 12 voltage which controlled by a relay hooked up to the ignition switch.
I have a fairly steep cart path going from my house down to my boathouse. My ‘96 TXT had no problem whatsoever making it up and down the path. The same held for the RXV – until recently.
It is starting to develop problems. Twice now while going up the path in the RXV with me and about (but no more than) 200 LBs (people and/or tools), there has been a loud bang/pop and the cart starts freewheeling backwards. The foot brake has no effect. It rolls couple of feet before the brake locks on. Once stopped, the ol’ turn off /turn on technique doesn’t work. I have to let it sit for a few minutes, then I can proceed up the hill. Each time I unload whatever is in it before trying it again. Each time the charge gauge shows at least ¾ charged. The other issue is that at times it can barely make it up the hill with just me onboard like it has super low voltage. Yet the gauge shows 3/4 or better charged. I only have had issues going up, never down.
This may be related. I’ve noticed that my charge gauge will go from showing ½ or better charged, to showing very low charge (but no low charge warning light) the next time it is turned on. I always check whenever I begin or finish using it in case it needs charging. Oddly, I’ve found the gauge will go from low charge to full charge in less than 5/10 minutes of being hooked up to the charger. Last time this happened I checked the batteries with a voltmeter, they all showed 12+ volts each.
This may not be related. Additionally, I found there is a noticeable pause (maybe 5 or 6 seconds) between the cart coming to a halt and the motor brake locking. This happens every time; doesn’t matter whether it’s going forward or backward or on a hill or level. I don’t know if that’s normal for a RXV.
These issues above may all be related, but most importantly I really need to find a fix to the motor suddenly “disconnecting” and it “freewheeling”. Any ideas or suggestions would be greatly appreciated.
Thanks, JW

[cartdoc1969]

Most likely the batteries are not getting fully charged.

Possibly a solenoid with failing contacts, check voltage at each large terminal to pack negative. They should be the same, if there's more than 1 or 2 volts difference then change the solenoid. Also inspect and clean all battery and controller connections.

The brake pedal not doing anything points to the controller loosing power because main braking is regen from the controller. The parking brake not engaging right away indicates to me a bad brake. I know you said it was replaced but with an OEM ? The parking brake on the RXV is one thing I wouldn't go aftermarket. When a factory brake locks it will almost throw you from the cart if your at speed. Even with a factory brake, the friction disk can be damaged from very few lock ups. It's main function is a parking brake but serves as a panic/emergency brake as well, but that will shorten it's life drastically.

[ojo]

A moving charge meter would be typical for one or more bad battery. Check each single battery, 12v is empty, you should see around 13v on each battery, all close together ( within .1 - .2v ).

What you described when rolling backwards, i know that. Has happend driving the cart Into the trailer. Problem is when the RXV stops, counter current ( regen ) braking stops working and there is a significant delay until the parking brake engage. With the panic brake functionality you'll be able to engage the parking brake immediately. You have to step on the pedal and push it to ca. 60% of travel to reach the brake switch attached to the assembly. That will cause the parking brake to engage.

Btw
Ezgo called it INTELLIBRAKE SYSTEM

[basshawk84]

It does sound like a battery issue to me, so as suggested make sure your charger is properly charging the batteries. Also, nothing should be hooked to the ignition switch on an RXV for fear of damaging the controller. The voltage reducer should be hooked to the controller side of the relay to get power.