New Holland T8010 Manual page 974

Blower Speed And Temperature Control Potentiometers ......................................................................... 50-1-45
Background ............................................................................................................................................. 50-1-45
Possible Failure Modes - Fault Codes 120, 121 ..................................................................................... 50-1-45
Electrical Test .......................................................................................................................................... 50-1-46
Common Control Potentiometer and Circuit Test Procedure .................................................................. 50-1-46
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
Section 50 - Climate Control - Chapter 1
50-1-3