1999 Buick Century 6 cyl Automatic 130000 miles
heater/cooling fan in cab works fine on a bench test, no noise of vibrations but instantly blows the 30 amp fuse in the passenger side when installed. Have read that may be indication of something wrong with AC
Are you talking about the high blower fuse? When testing, you can use a testlite across the fuse terminals, instead of blowing all your fuses. If the lite comes on, the circuit is going to ground. Unplug blower motor and test, if it still comes on, unplug connector at resistor assembly test again. It might be a short on the circuit from fuse to resistor assembly?