I left my van for two weeks; thought I had turned off all loads. Came back and all displays are flat - Kisae DMT1250 doesn’t respond with engine running, Victron 702 screen is blank. No charge accepted with engine on. Hooked a battery charger directly to cable leads to the battery with no result. How do I restart the BMS? Apparently everything drained and hopefully the BMS low voltage protection kicked in. Where to go from here?
I connected it to another 12v battery via jumper cables, and let it sit for about 10 seconds. I then hooked the battery charger up and it charged. So I needed to trick the BMS with the other battery, i guess.
I would assume the BMS would keep it from 100% discharge, no? battery chargers wouldn’t recognize it, so I hooked it with jumper cables to another 12v battery and let it sit for a couple minutes, That woke up the BMS and it charged up again.
there are 2 reasons maybe cause this:
the first maybe low temperature cut off BMS, try with a 12v charger when temperature back to normally.
the second reason maybe it's 100% completely discharged, you could try with a 12V battery charger to charge it back.
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