RXV accelerates after lifting off pedal

[carter95138]

I new problem just popped up.

I just installed the Allied Lithium Batteries in my cart (4x12v, 50Ah). After a full charge when I leave my house, I head down hill to the golf course. When I get to the point where I need to slow down to turn into the driveway I lift off the pedal and press the brake (I still haven’t confirmed if this happens before or after I touch the brakes) and the cart continues to accelerate. The only way to stop it is to mash the brakes and turn the key to Reverse or Off. Then it corrects itself. It has happened a couple of times and I was able to confirm putting the key in Neutral doesn’t work. It has to be in R or OFF.
It only happen right after I have unplugged it from the charger. It has never happened on the golf course. I also unplugged the charger the day before to let the batteries “settle” the voltage and that seems to have worked. FYI, battery voltage right after unplugging from the charge is 58v+. It will settle down to 56v or so if I leave it for a few hours.
I’m going to bring it to our tech at the club to have him read for any error in the computer.

Any clues? Resistor or +/- 8 ohms

Thanks.

[BobBoyce]

Originally Posted by carter95138

I new problem just popped up.

I just installed the Allied Lithium Batteries in my cart (4x12v, 50Ah). After a full charge when I leave my house, I head down hill to the golf course. When I get to the point where I need to slow down to turn into the driveway I lift off the pedal and press the brake (I still haven’t confirmed if this happens before or after I touch the brakes) and the cart continues to accelerate. The only way to stop it is to mash the brakes and turn the key to Reverse or Off. Then it corrects itself. It has happened a couple of times and I was able to confirm putting the key in Neutral doesn’t work. It has to be in R or OFF.
It only happen right after I have unplugged it from the charger. It has never happened on the golf course. I also unplugged the charger the day before to let the batteries “settle” the voltage and that seems to have worked. FYI, battery voltage right after unplugging from the charge is 58v+. It will settle down to 56v or so if I leave it for a few hours.
I’m going to bring it to our tech at the club to have him read for any error in the computer.

Any clues? Resistor or +/- 8 ohms

Thanks.

It sounds like you never had your controller reprogrammed for the new nominal voltage of the lithium pack. That condition can affect the controller. Default nominal voltage is set at the factory for 48V and it can handle up to 56V without reprogramming. Exceeding that will cause an overvolt condition.

Bob

[carter95138]

That does sound like the problem. I’m having the computer checked for errors on Tuesday. If that is what he is seeing, he should be able to fix it.

If he can reprogram the computer, what should he change.

After they have been fully charged, with the charger still attached the batteries are at 58.3v.
After unplugging and letting them set for 20-30 min, the voltage levels off at 57.9 (tho I usually just unplug the cart and head right for the golf course)
After a full round of golf and letting the batteries set for 30-60 min, they are at around 53v.

I’ll post a response after the tech looks at the cart.

Thanks for your feedback.