one of those contacts is for the headlight circuit, one for the rear lights - if the bi-metal is melting you have an extreme draw on the headlights, like bad insulation on a wire maybe, or a bad dimmer switch as suggested
"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
