Control Assembly: Testing and Inspection
A/C HEATER CONTROLSThe operation of the recirculation door can be viewed by removing the blower motor and looking up into the HVAC housing.
1. Connect the test set vacuum probe to the heater-A/C vacuum supply (Black) hose in the engine compartment. Position the test set gauge so that it can be viewed from the passenger compartment.
2. Start with the mode control in the Panel position and the recirculation control in the Outside-air position.
3. Move the recirculation control to the Recirculation position (the recirculation door should move into the Recirculation position). After a short pause move the mode control to the Defrost position (the recirculation door should move to the Outside-air position). The test gauge should return to the calibrated setting of 27 kPa (8 in. Hg.) after each selection is made. If the gauge cannot achieve the calibrated setting, the vacuum circuit or a component has a leak.
4. If the gauge achieves the calibrated setting but the door does not move, there is either a pinched vacuum line or a failed actuator.