yeah, check that. also, you may have a short else where, like the contactors in the switch. was the switch used? it seems like all Cherokees do this, including mine. so if it was a used switch it could be bad. the switch also could have shorted out during installation. pull it out and do a resistance check on the switch, blower motor, and resistor. basically, start from the switch and work your way down.check the blower motor resistor.