There are no vacuum lines that control the vent modes. There are 4 mode actuators located under the dash and are known for stripping the plastic worm gear or reduction gear. 1 on on the drivers side and 3 on the passenger side. Most of them are a pain to replace. The driver side one which controls the panel/floor is extremely difficult. The defrost one isn't too hard but a pain none the less. I've had to replace 3 of the 4 so far. Use only Ford genuine parts. The aftermarket units (Dorman) don't last. Ford made improvements.
Blend & Inlet door part# YH1865
Panel/Floor part#YH1869
Defrost part#YH1870
I bought my last units from Rockauto.com.
Heat & Air Conditioning Parts and More for Your 2006 FORD MUSTANG at Reliably Low Prices. Fast Online Catalog. DIY-Easy. Your Choice of Quality. Full Manufacturer Warranty.
www.rockauto.com
Ford Workshop Service and Repair Manuals, 2005 Mustang Workshop Manuals Electrical Climate Control System Climate Control Replacement, Removal and Installation Mode Door Actuator Air Inlet Door
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