Test H: Incorrect/Erratic Direction of Air Flow From Outlet - EATC

PINPOINT TEST H: INCORRECT/ERRATIC DIRECTION OF AIR FLOW FROM OUTLET - EATC

H1-H4:

H4-H6:

H7-H8:

H9-H10:

H11-H14:

H14-H15:

H16-H17:

Normal Operation
Under normal operation, the electronic automatic temperature control (EATC) module is provided vacuum from the engine. When a mode is selected, vacuum is applied to the desired vacuum control motor that is connected to the mode door you want to control.

Possible Causes
- Electronic automatic temperature control (EATC) module
- Heater control valve
- Vacuum control motor
- Stuck or bound linkage or door
- Leaking or plugged vacuum hose