ive found tht msot of the resistors fail on my car after a couple years of being blasted with rain and whatever else makes it through the radiator. i jsut make sure i have one NIB at home waiting for the next one to fail. 50 bucks every couple of years isnt so bad. (its more like a preventative maintanence thing. i jsut do it by habit now. )
your car will never be like my car, after all you have common sense......