I’ve fitted a battery to my J35, but it’s not detected by my BMPRO battery monitor?

Check the following:

• The battery connections are tight and not loose or corroded.
• Battery polarity: red lead is positive, black lead is negative.
• The dealership fitted in-line fuse with the caravan battery is fitted and not blown. The correct value is 40A.
• The battery fuse on the J35 is fitted and not blown. The correct value is 40A.