Seat caught on fire

98 Bravada driver seat heater some how shorted out and caught the seat on fire while the car was unattended (ignition off). Is there power to the seat heater when the ignition is off?

i've seen this same problem posted before either here or on the old forum. the answer is yes, most devices on modern vehicles with negative ground electrical systems have power supplied to the device all the time with the path to ground interupted by a switch. if you get a short to ground, such as your seat heater wiring rubbing against the frame of the seat you've got a problem.

on all of my vehicles i install a quick disconnect on the negative side of the battery. it probably wouldn't have helped in your situation, but has saved my butt a couple of times when i caused a short and was able to shut it down before the whole wiring harness was destroyed.