A simple question with what I hope will be a quick and easy answer.
My BMV-712 Smart Monitor is no longer working after removal and replacement of my (monitored) 12V battery - it has no display. Before I start dismantling anything, I’d like to know what is the voltage I should be seeing on the power cable that is connected to the plug on the shunt. I know one end is connected to the positive battery terminal but on the other end (the end with the ferrule that plugs into the shunt fitting) I’m seeing 3.3V.
I realise now the mistake I’ve made. It’s a DIY LiFePO4 battery and I’d dismantled it to perform a top balance. When I reassembled it I must have incorrectly attached the monitor power lead to the positive of cell 1 instead of cell 4. That explains the presence of the cell voltage and not the battery voltage. I will now take the cover off and instead of attaching the power lead INSIDE the case and threading the crimped end through a hole in the case cover, I’ll attach it to the positive terminal like most sensible people would do
That way, not only am I guaranteed to connect to the battery positive, I can also easily replace the inline fuse should it fail. So much for my idea of making the battery look a bit less cluttered! It’s come back and bit me in the bum.
