the click itself may not indicate any problem, but if there's a spark when you first touch the cable to the batt post, you do have something wrong, indicating a drain will be happening - could be your broken ignition switch?
"When we tug a single thing in nature, we find it attached to the rest of the world" ~ John Muir "When we tug a single thing on an old truck, we find it falls off" ~ me Some TF series details & TF heater pics