Under your battery tray
The vacuum switch/actuator for the fan shutter is under the dash directly below the radio . IT is NOT easy to get to.
The heater blend door is not run by vacuum. It is run by an electric actuator.
Remove the dash assembly to gain access to the blend door actuator.
how to replace actuator on a 2000 malibu
No, it is electric
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The 1997 Chevrolet blazer actuator switch is located on the firewall in the engine compartment. The switch is on the passenger side of the engine compartment.
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