Service Manual
Table Of Contents
- 627333-A
- 01 Introduction
- Safety
- Follow Safety Instructions
- Prepare for Emergencies
- Safety Alert Symbol
- Signal Words
- Informational Messages
- Important Safety Information
- General Hazard Information
- Emergency Exit From Cab
- Operating The Vehicle Safely
- Prevent Vehicle Runaway
- Use Safety Lights and Devices
- Operating On Slopes
- Traveling On Public Roads
- Stopping And Parking The Vehicle
- System Boom Safety
- Avoid Eye Contact With Radar
- Exhaust Fumes
- Overhead Electrical Power Lines
- Noise
- Handle Fuel Safely - Avoid Fires
- Stay Clear Of Rotating Drive Lines And Moving Parts
- Towing Other Vehicles / Trailers / Equipment
- Modifications
- Maintenance And Service Safety
- Practice Safe Maintenance
- Chemical Safety
- Wear Protective Clothing
- Work In A Clean Area
- Understand Correct Service
- Use Proper Tools
- Support Machine Properly
- Proper Lifting Equipment
- High-Pressure Fluids
- Hydraulic Hoses
- Avoid Heating Near Pressurized Fluid Lines
- Service Cooling System Safely
- Remove Paint Before Welding Or Heating
- Batteries
- Tires And Wheels
- Dispose Of Waste Properly
- Mobile Radio Installations
- Maintenance In The Articulation Joint (Hinge) Area
- Safety Tread and Grip Material
- Safety And Service Decal Locations Chassis
- Safety And Service Decal Locations Cabine
- General
- Dimensions
- Torque Specifications
- Jack Up The Machine
- Tooling list
- Index
- Safety
- 02 Engine
- 03 Powertrain
- Transmission Service Manual
- Transmission and Solenoids
- Testing and Adjusting
- Transmission Troubleshooting
- Disassembly and Assembly
- Drive line
- Index
- TA19 KENR6054-00
- TA19 KENR6678 (Modification)
- 04 Chassis
- MM9L(Modification)
- 05 Cab
- Cab
- Cab Seat
- HVAC
- General Information
- Theory of operation
- Basics of Refrigeration
- Air Conditioning Process
- HVAC System
- Automatic Temperature Control
- Refrigerant Relief Valve
- Temperature Sensors
- Evaporator Coil
- Heater Core (Cab)
- Actuator Motor (Water Valve)
- AirFlow
- Motor (Air Conditioning Blower)
- Speed Control
- Actuator Motor (Damper)
- Glossary of Terms
- HVAC Specification
- HVAC Testing and Adjusting
- Troubleshooting Machine Preparation
- General Troubleshooting Information
- Visual Inspection
- Troubleshooting Faults With Service Codes (Active)
- Troubleshooting Air Conditioner Control
- Problem List
- Probable Causes
- No Display
- Probable Solution
- No Blower Fan
- Probable solution
- No Heat
- Probable Solution
- No Cooling
- Probable Solution
- System is putting out cool air when heat needed
- Probable Solutions
- System is putting out hot air when cooling needed.
- Probable Solution
- No Fan or Erratic Fan
- Probable Solutions
- Nothing Works
- Probable Solution
- Electric Actuator for Mode of Airflow is not Moving or Working Properly
- Probable Solutions
- Refrigerant Compressor Oil - Check
- Refrigerant System - Charge
- Complete Charge of System from a Refrigerant Tank with a Scale
- Adding Additional Refrigerant to an Air Conditioning System with Low Charge
- Manifold Gauge Set (Refrigerant) - Remove
- Control Panel - Test
- Index
- 06 Electrical
- 07 Hydraulic
- 08 Air System
627333-A 5-41
HVAC Testing and Adjusting
TROUBLESHOOTING AIR CONDITIONER
CONTROL
Problem List
Problems listed below are discussed in more detail.
•No display
• No blower fan
• No heat
• No cooling
• System is putting out hot air when cooling is
needed.
• No HVAC system function
• No fan or erratic fan
• Electric actuator for airflow is not moving or working
properly.
Probable Causes
The following offers problems and a probable solution:
No Display
1. Turn control panel on with mode switch.
2. Check display for illumination.
3. Verify control panel is connected properly.
4. Check connection of wire harness to unit.
5. Verify control panel is receiving 12 volts of power.
6. Verify control panel is properly grounded.
Probable Solution
1. Replace control panel.
No Blower Fan
1. Turn blower fan to high.
2. Ensure blower fan is connected properly.
3. Verify circuit breakers and fuses are in tact.
4. Verify HVAC unit is receiving 12 volts of power.
5. Verify blower motor is receiving 12 volts of power.
6. Verify blower motor is properly grounded.
Probable solution
1. Replace fuse or circuit breaker.
2. Replace blower motor.
3. Replace electronic control module.
No Heat
1. Turn up heat with control button.
2. Verify warm coolant is flowing into heater core by
testing heater hoses.
3. Verify water valve is working correctly.
4. Inspect water valve for jammed components.
Probable Solution
1. Replace water valve.
No Cooling
1. Turn down heat with control button.
2. Turn mode switch to enable defrost.
3. Verify refrigerant compressor has voltage at clutch.
4. Verify circuit breakers and/or fuses are intact.
5. Verify relay for clutch on wire harness has voltage.
6. Verify system is fully charged with refrigerant.
7. Verify heater valve is closed
Probable Solution
1. Inspect relay for clutch. If necessary, replace relay.
2. Replace heater valve.
System is putting out cool air when heat needed
1. Verify temperature sensor for cab airflow is
connected correctly.
2. Verify water valve is working properly. refer to No
Heat for additional information.
Probable Solutions
1. Replace temperature sensor for cab airflow.
2. Replace control module.
System is putting out hot air when cooling
needed.
1. Verify temperature sensor for cab airflow is
connected correctly.
2. Verify water valve is working properly and water
valve is not stuck open.
3. Verify compressor clutch is working properly, refer to
No Cooling for additional information.
Probable Solution
1. Replace temperature sensor for cab airflow.
2. Replace control module.
No Fan or Erratic Fan
1. Set rotary control for blower fan to maximum.
2. Ensure blower fan is connected properly.
3. Verify circuit breakers or fuses are intact.
4. Verify HVAC unit as 12 volts of power.
5. Verify blower motor has 12 volts when rotary control
is at maximum.
Probable Solutions
1. Replace blower motor.
2. Replace control module.