I've replaced 3 blower motors in the last few months. I've made sure that the plug wires are +2 inches from the housing. The supply voltage is correct. The ground is perfect. Here's the problem. The service manual states the variable voltage should vary between 4 and 9 volts for low to high operation. The voltage I get is .8=high and 1.5=high. Other than this oddity, the fan operates normally other that they die every few weeks. One only lasted a week. Electrically, this voltage shouldn't cause the blower to die, but either I've gotten a bad run of blowers or something else is amiss. Any help is greatly appreciated. Thanks.