Service Manual

5-ii 627333-A
Contents
Intake For Airflow .............................................................................................................................. 5-23
Fresh Air ............................................................................................................................................ 5-24
Recirculation ...................................................................................................................................... 5-24
Head, Foot and Defrost ..................................................................................................................... 5-25
Motor (Air Conditioning Blower) ............................................................................................................... 5-25
Overpressure blower ......................................................................................................................... 5-25
Automatic Temperature Control (Fan) ............................................................................................... 5-26
Manual Fan Control ........................................................................................................................... 5-26
Speed Control .......................................................................................................................................... 5-26
Automatic Fan Speed Control ........................................................................................................... 5-26
Manual Mode Fan Speed Control ..................................................................................................... 5-26
Actuator Motor (Damper) ......................................................................................................................... 5-27
Glossary of Terms ................................................................................................................................... 5-28
HVAC SPECIFICATION
Refrigerant Compressor .......................................................................................................................... 5-33
Compressor ....................................................................................................................................... 5-33
Clutch ................................................................................................................................................ 5-33
Relief Valve ....................................................................................................................................... 5-33
Belt .................................................................................................................................................... 5-34
HVAC TESTING AND ADJUSTING
Troubleshooting Machine Preparation ..................................................................................................... 5-35
General Troubleshooting Information ...................................................................................................... 5-36
Visual Inspection ...................................................................................................................................... 5-36
Troubleshooting Faults With Service Codes (Active) .............................................................................. 5-37
Service Codes ................................................................................................................................... 5-37
Entering Active Troubleshooting ....................................................................................................... 5-37
Troubleshooting Using Active Diagnostics ........................................................................................ 5-38
Checking Temperature Sensors ........................................................................................................ 5-38
Checking Compressor Clutch ............................................................................................................ 5-38
Checking Refrigerant Pressure Switches .......................................................................................... 5-39
Checking Actuator for Water Valve ................................................................................................... 5-40
Checking Blower Fan ........................................................................................................................ 5-40
Checking Mode Door Actuator .......................................................................................................... 5-40
Troubleshooting Air Conditioner Control .................................................................................................. 5-41
Problem List ...................................................................................................................................... 5-41
Probable Causes ............................................................................................................................... 5-41
Refrigerant Compressor Oil - Check ........................................................................................................ 5-43
General .............................................................................................................................................. 5-43
Complete Check of Compressor Oil .................................................................................................. 5-43
Refrigerant System - Charge ................................................................................................................... 5-44
Relationship Between Temperature and Pressure (R-134a Refrigerant) .......................................... 5-44
Labeling Procedure ........................................................................................................................... 5-47
Charging System ............................................................................................................................... 5-47
Complete Charge of System from a Refrigerant Tank with a Scale ........................................................ 5-48
Adding Additional Refrigerant to an Air Conditioning System with Low Charge ...................................... 5-50
Manifold Gauge Set (Refrigerant) - Remove ........................................................................................... 5-50
Control Panel - Test ................................................................................................................................. 5-51
Test Automatic Control Panel ............................................................................................................ 5-51
INDEX ......................................................................................................................................................... 5-53