T8010/T8020/T8030/T8040 MASTER TABLE OF CONTENTS BLOWER AND BLOWER SPEED DRIVER ............................................................................................. 50-1-47 Background ............................................................................................................................................. 50-1-47 Power, Signal and Ground Circuit ........................................................................................................... 50-1-47 Possible Failure Modes ...........................................................................................................................
50-1-47 Blower Motor/Blower Driver Power, Signal and Ground Test ................................................................. 50-1-48 Cab And Evapator Temperature Sensors ................................................................................................. 50-1-49 Background ............................................................................................................................................. 50-1-49 Electrical Test ..........................................................................................................................................
50-1-51 Power Circuit ........................................................................................................................................... 50-1-51 Possible Failure Modes - Fault Codes 111, 115 and 116 ....................................................................... 50-1-52 Cab Temperature Sensor and Circuit Test ............................................................................................. 50-1-53 Evaporator Temperature Sensor and Circuit Test ..................................................................................
50-1-54 Controller Power, Ground, And ATC Switch ............................................................................................. 50-1-56 Background ............................................................................................................................................. 50-1-56 Power and Ground Circuit ....................................................................................................................... 50-1-56 Possible Failure Modes ...........................................................................................................................
50-1-56 Controller Power Supply and Ground Test ............................................................................................. 50-1-56 ATC Switch and Circuit Test ................................................................................................................... 50-1-57 Defog/Defrost Switch and Circuit Test .................................................................................................... 50-1-57 Cab Pressurizer Blower ............................................................................................................................
50-1-58 Background ............................................................................................................................................. 50-1-58 Power and Ground .................................................................................................................................. 50-1-58 Cab Pressurizer Blower & Relay Power Supply and Ground Test .......................................................... 50-1-58 ACCESSING THE HVAC BOX .................................................................................................................
50-1-59 STANDARD AIR CONDITIONING (STD) TROUBLESHOOTING ............................................................ 50-1-60 Standard A/C Operation ............................................................................................................................ 50-1-61 Smart Pressure Switch Cycling System .................................................................................................. 50-1-61 Standard A/C Controls and Their Function ............................................................................................. 50-1-62 Symptom-Based Standard A/C Troubleshooting ......................................................................................
50-1-63 Standard Controller Test ........................................................................................................................... 50-1-65 Compressor And Clutch ............................................................................................................................ 50-1-67 Operational Check .................................................................................................................................. 50-1-67 Electrical Test – Compressor Clutch .......................................................................................................
50-1-70 Clutch Relay Power Supply and Ground Test ......................................................................................... 50-1-71 Service Note: Adjusting Clutch Air Gap .................................................................................................. 50-1-72 High And Low Pressure Switch Clutch Latching Circuit ............................................................................ 50-1-73 Background .............................................................................................................................................
50-1-73 Possible Failure Modes - Flashing Pressure Warning Lamp .................................................................. 50-1-74 Electrical Test – Pressure Switches ........................................................................................................ 50-1-75 High Pressure Switch and Circuit Test .................................................................................................... 50-1-75 Low Pressure Switch and Circuit Test ....................................................................................................
50-1-76 Heater Control Valve ................................................................................................................................. 50-1-77 Operational Check .................................................................................................................................. 50-1-77 Electrical Test .......................................................................................................................................... 50-1-78 Temperature Control Potentiometer .........................................................................................................
50-1-79 Background ............................................................................................................................................. 50-1-79 Electrical Test .......................................................................................................................................... 50-1-79 Blower Speed Switch And Blower Motor .................................................................................................. 50-1-80 Background .............................................................................................................................................
50-1-80 Power and Ground Circuit ....................................................................................................................... 50-1-80 Possible Failure Modes ........................................................................................................................... 50-1-80 Blower Speed Switch and Power Circuit Test ......................................................................................... 50-1-81 Blower Motor Power, and Control Circuit Test ........................................................................................ 50-1-81 10