Gerard, how is your dual battery system set up? If it has a battery isolator connected between the cranking battery and the auxiliary then there will be no problem.
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PeterD Nissan Navara D23 diesel auto, Spaceland pop-top Retired radio and electronics technician. NSW Central Coast.
yes I have an isolator between the two batteries.
what I did this morning is put a switch on the earth of the isolator so I can turn it off when recharging each battery. it seems to work ok. time will tell