Under Voltage Notification

I’m definitely a noob but am looking for some direction before I take my system in for repair. I am currently not able to charge my system with either solar or shore. I am getting a notification alarm of “A-B11: Under Voltage” for my Smart BMS PD4? My system consists of:

Victron 12v 200 Ah LiFePo4 Smart Lithium Battery (3)

-Victron Multiplus 12/3000/120-50 120V Inverter/Charger

-Victron Smart BMS CL 12-100

-Victron Smart Solar MPPT 100/50 Charge Controller

-Victron Smart Battery Protect 12/24-100A

-Victron Smart Battery Protect 12/24-65A

-Victron Smart Shunt 500A/50mV

-Victron Cerbo GX

-Victron GX Touch 50

-WFCO Combination Breaker/Fuse Panel 110V/12V

-BlueSea Passenger Side 12V Compact Fuse Panel

I keep the van in storage so I take it out periodically to charge via alternator/solar. I was down to 76% and two days later it was dead. I may have left something on? I have been unable to get it to take a charge since. I am planning on taking it into a local service center but wanted to see if I could get a better understanding of what I may be dealing with first. Thanks for the help!

Undervoltage should not disable chargers, perhaps the control wiring is wrong, perhaps one of the battery comms cables has become loose / damaged, perhaps the batteries have discharged so low that they will no longer communicate, the if the system is wired correctly the battery protects should have shut down.

Have you measured the battery voltage with a multimeter. That would be the most obvious first step to dimensioning the problem.

The battery manual covers troubleshooting in Section 6.