2006 Hummer H3 Heater no longer turns on (no noise at all)

It may be the blower motor resistor, and quite possibly the blower motor itself. But before we rule any of those, please check these fuses and relays first.

If they are all OK, then replace your resistor.

Typically, the orange power wire terminal in the resistor connector gets hot and opens up. The resistor is under the rh side of the dash, the connector is red(5-6 pin). Try and disconnect it to check. If it is melted, you need to replace the terminal, connector body, and resistor.

I recently had the same issue where one minute the heater blower worked and the next it did not. I called my mechanic who said it could be a fuse (it was not), the resistor, or the motor itself. I checked the fuses and all were good. I tapped the blower motor about a dozen times and all of a sudden it began to work. It appears that the bushings wear and sometimes the motor has difficulty getting enough torque to start. It works now but the long term solution is a new blower motor and I will likely change the terminal and resistor at the same time.

Our 2006 did the same thing, no blower. We replaced the resistor that is under the dash. Auto Zone part, 40+-$. The harness was melted to the white plastic casting because of the heat at the orange terminal. There is a white plastic retaining pin at the harness plug you have to remove to seperate the resistor. My harness was black but I was able to scrape it clean enough to make a sort of connection and the blower began to work as the harness connectors were jiggled. Now to wait for The national highway administration to recall this as it is a fire hazard. Mine is working for now but I am sure the symptoms will reapear as a full fix and it is a defective design.