The above is correct. The smart charger needs to see voltage from the charging battery. When that happens I usually use jumper cables from a charged battery and connect the smart charger on the dead battery. Then after a short while remove the jumpers.
Barbara and Laurent, Hartland Big Country 3500RL. 39 ft long and 15500 GVW.
2005 Ford F250 SD, XL F250 4x4, Long Box, 6.0L Diesel, 6 Speed Stick, Hypertech Max Energy for Fuel mileage of 21 MPusG empty, 12.6 MPusG pulling the BC. ScangaugeII for display..