XRV not charging. New BMS wasn’t the fix

Several weeks ago, I came back from riding and plugged in the board. The light on the charger stayed green and the board wouldn’t charge… the board is fully functional at 36%. You can still ride it, but it’s bound to die.

  • We tried two different chargers and both hadn’t worked

We contacted Tony for a new BMS and a few days later we got it! We were sure this would solve the issue. We put the new one in, and nothing changed whatsoever.

Any help or ideas would be appreciated

I’ve had this issue before with my non-XRV VESC. Check your Molex connector, mine had wiggled loose enough to interfere with charging and yet the board still operated normally. Once I pushed the connector back in, the board started charging normally. I adjusted the wiring harness to prevent tension from pulling the connector back out again.

To verify connections, have you traced the voltage from the Charger Output through the charge port, harness, into the BMS Charger Input? does it look OK?
Does the BMS provide cell level monitoring? Is it turning on? Are the cells all OK?
it’s possible something is wrong with the pack and the BMS is refusing to charge. You can manually check the voltage of each cell pgroup at the balance connector carefully.

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Do you have a multimeter? With harness completely disconnected, you need to continuity check the small wires in the harness that are used for charging. They are fragile so likely one became damaged.

We have a multimeter, how should I go about doing this, can I have a more detailed description on how to check the continuity?

Select continuity mode or ohms mode on meter. One probe to small wire on bms connector end, other probe to molex connecter end. Meter should beep or less than 0.1 ohm on every wire. Check all the small wires that go to the bms. Might need to alligator clip probe to smaller size piece of wire to reach contacts in connector if probe is too big to fit