The battery monitor on my 06 P Thunder left much to be desired. It is a Magnum and provides little in the way of desired info. I had installed, by Jeff at Bend RV, a new Victron BMV-702 monitor. I put the round gauge in the aft master bedroom next to the TV so wiring was a short straight snap. This morning I drove by the storage lot, did not unlock and open the gate just drove by near the coach location, turned on my cell phone app and read the charge status of both the house and chassis batteries, current draw (-.85 amp with no solar contribution, .56 amp in when the sun came out) Gave me total amps down since last full charge and will give me both time remaining at current draw and time to recharge when amps are positive. Cost of device was less than $300. BTW, the Magnum stuff up inn the bow above the entry steps is unaffected and still functions normally.
