 they've been known to get bad and not make a good connection. And sometimes when you're moving it around, even it'll take off and start running, but check the power and ground right at the motor with everything connected and everything turned on high and see if you have voltage. You should have battery voltage there with it running. It should be at least 13 volts right there. If you don't have voltage, then you've got to keep moving backwards till you find it. Go to that blower resistor, which is that module close to the, it's located close to the blower under the dash and,