Ventilation Air Flow System

Mode Selection Chart:

VENTILATION AIR FLOW SYSTEM
1. With the ignition switch ON, set the heater blower motor switch set to position 4 for maximum air flow.
2. Check the air flow patterns resulting from the position settings of the mode selector using the "Mode Selection Chart".
3. Verify that they conform to the specified air flow patterns as listed in the appropriate diagrams:

FLR/DEF Mode Diagram:

DEF Mode Diagram:

Panel and Recirc Mode Diagram:

Panel/FLR Mode Diagram:

Floor Mode Diagram:

(1) Defrost/Floor Control Door
(2) Heater Core
(3) Temperature Control Door
(4) Vent Function Control door
(5) A/C Inlet Door
(6) A/C Blower Motor

4. If air flow patterns do not conform to the specified patterns, repair, adjust, or replace the outlet doors or components as required.

Inlet Air Chart:

5. With the ignition switch ON and the blower motor switch set to position 4 for maximum air flow, change the function control lever setting from RECIRC to any other position. Verify that the air movement conforms to the specified patterns listed in the "Inlet Air Chart".
6. If air does not conform to pattern, repair, adjust, or replace the A/C blower motor or inspect control cables and linkages for kinks or damage.
7. Disassemble the following components of the ventilation system for inspection as required, and remove any foreign material causing air flow blockage:
^ A/C blower motor
^ A/C evaporator housing
^ Recirculation inlet
^ Fresh inlet
^ Main air duct (No A/C)
^ Evaporator (With A/C)
^ Heater core inlet side
^ Air outlets at floor, panel, and defroster
8. If air flow is inadequate in any position, adjust the A/C air inlet door, defrost/floor control door, temperature control door, or vent function control door as required. Otherwise, return to the Pinpoint Tests.