question

drester228 avatar image

BMV 712 reports wrong voltage on engine starter battery all good otherwise.

8 house batteries on sailboat are being reported correctly by BMV 712, engine crank battery is always low versus reading direct at battery with meter.

battery charging
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We need some more information about your system. What other components do you have? How are the batteries connected to each other?

1 Answer
Paul B avatar image
Paul B answered ·

check the voltage at the Shunt were the small red wire plugs in for Aux 2 input, it should read the same as at the battery positive. if it does not then replace that wire or check connections.

Also when checking voltages always check the negative cable as well.

put the Negative cable from your meter on the shunt and then move it to the battery negative of the starter battery,

the voltage readings should also always be the same. if not then you have a voltage drop in the negative cable between the shunt and the starter battery.



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