Troubleshoot my nonfunctional, brand new,
Blower motor - all tests with key in and on, fan motor set to 4....
Tested the input to the fan, with the switch on, and sweeping through all settings other than Off.. 0 volts.
Checked the main fuse and relay underhood.
Removed and checked for continuity through the fuse. Good to go. Reinstalled.
Swapped the radiator fan and blower motor relays. No change.
Checked all the fuses on the driver's dash end cap, with the lights turned on. One lead to the door check (decent ground), and the other probing the recessed contact on each side of the fuses. All passed.
At this point, it is about 99.8% sure to be the resistor pack. New one arrives Thursday. Frankly I'm a bit pissed the last only lasted 3 months.