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Hummer H3For the Hummer driver who wants the rugged look and off road capabilities of the Hummer, but in a smaller size and with a more fuel economy friendly engine.
My H3 only blows full cold and will not provide heat. I've searched so I have a good idea of the components that make up the heating system.
1. Coolant system is full and topped off. Both heater lines feel hot to the touch.
2. Thermostat appears to be functioning. Vehicle temperature is normal around the halfway mark.
3. Performed A/C calibration test. System cycled through all the different positions but still no heat.
4. Removed heater blower fuse and it looks fine. Nothing burnt.
5. Looked under the dash and only the top actuator moves when changing the different airflow positions. Bottom two actuators do not move with any of the A/C dials are adjusted.
I find it hard to believe that both actuators would go bad at the same time—is there something in the system that ties these two actuators together that I could check? Or should I just proceed to changing these both out?
Hummer H3 no heater
