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?
Greg
It seems like your battery's BMS (Battery Management System) has likely triggered its low-voltage protection to prevent damage from over-discharge. To restart the system, begin by checking the battery voltage with a multimeter to confirm whether it is below the BMS cutoff level. If so, you may need to "wake up" the BMS. Some systems allow for a temporary bypass to reactivate the battery, so consult your battery’s manual for specific instructions. Alternatively, connecting a low-amperage charger (1–2A) directly to the battery terminals can sometimes raise the voltage enough to reset the BMS. Ensure all cable connections are secure and free of corrosion, as poor connections can also prevent charging. If the BMS resets but your Kisae DMT1250 and Victron 702 remain unresponsive, inspect fuses, wiring, and device settings for possible issues. If these steps do not resolve the problem, it’s best to contact the battery or BMS manufacturer for further assistance. Once your system is restored, consider reviewing all loads and charging setups to avoid similar issues in the future, ensuring uninterrupted use for tasks like powering up your system or enjoying a game on iOS while on the road