Lithium Battery RXV won’t tow
 

2016 RXV with a Lithium pack I installed
I ran out of Juice on the way home. Cart would not move in tow mode. Tried changing the plugs(1,2 3,4 and switched them) as normal when I had lead acid batteries. Cart would still not move, brake would not disengage. Only other thing I didn’t try was taking off motor brake.
Ended up running extension cords from a neighbor and getting enough charge to get it home.
Question is what to do if this happens again? Anyone know how to make it move it this happens again?

Re: Lithium Battery RXV won’t tow
 

When the battery is in protection mode it's fully disconnected and hence your EMB is stuck on. The only way to make it move again is to get the battery out of protection mode as you found out.

Re: Lithium Battery RXV won’t tow
 

In a nutshell, the motor brake/parking brake is spring loaded and defaults to locked by design. That way it's not drawing power as it sits parked. It only releases when power is applied, so no power = no release. Have to either find a way to provide 48v+ to the brake or remove it from the end of the motor.

Re: Lithium Battery RXV won’t tow
 

You need to find out how you reset your battery when the BMS cuts power. The brake won't release if the battery is shut down by the BMS. This is a bad feature of the RXV unfortunately.

Re: Lithium Battery RXV won’t tow
 

Some batteries require connection to a charger to turn back on. You can achieve this in the field with a 12v car booster connected to a 12v to 58v current limited boost converter set to about 1/2 an amp. It will not be enough to give it enough charge to get moving under its own power but it will switch the battery back on and release the EMB in tow mode.

Re: Lithium Battery RXV won’t tow
 

Thanks everyone for the replies. Kind of what I thought I was dealing with. Best bet is to try not to run out of juice again. Haha don’t trust state of charge app is what I realized.

Re: Lithium Battery RXV won’t tow
 

Many state of charge apps / meters are very inaccurate. I have a speedometer / odometer in my cart along with SOC so I know how far I can drive before needing to charge. You need to be conservative - especially with an RXV cart due to the violent event that happens when the battery cuts out.

Re: Lithium Battery RXV won’t tow
 

Get yourself the Renogy 500A SOC meter with shunt. Accurate when connected correctly.

Re: Lithium Battery RXV won’t tow
 

I have had this exact same thing happen a couple of times. I disconnected a negative battery cable. When I go to re attach it, it will spark and wake the system up. You can then put it in tow. O carry a 13 mm wrench to do this.