AUTO 157 - Heating and Air Conditioning Level 2

1. Complete general A/C System diagnosis and Repair Level 2 NATEF tasks.
   1. Identify and interpret heating and air conditioning problems; determine necessary action.
   2. Research applicable vehicle and service information, vehicle service history, service precautions, and technical service bulletins.
   3. Performance test A/C system; identify problems.
   4. Identify abnormal operating noises in the A/C system; determine necessary action.
   5. Identify refrigerant type; select and connect proper gauge set; record temperature and pressure readings.
   6. Leak test A/C system; determine necessary action
   7. Inspect condition of refrigerant oil removed from A/C system; determine necessary action.
   8. Determine recommended oil and oil capacity for system application.
   9. Using a scan tool, observe and record related HVAC data and trouble codes.
2. Complete Level 2 NATEF tasks related to Refrigeration System Components.
   1. Inspect and replace A/C compressor drive belts, pulleys, and tensioners; determine necessary action.
   2. Inspect, test, service or replace A/C compressor clutch components and/or assembly; check compressor clutch air gap; adjust as needed.
   3. Remove, inspect, and reinstall A/C compressor and mountings; determine recommended oil quantity.
   4. Identify hybrid vehicle A/C system electrical circuits and the service/safety precautions.
   5. Determine need for an additional A/C system filter; perform necessary action.
   6. Remove and inspect A/C system mufflers, hoses, lines, fittings, O-rings, seals, and service valves; perform necessary action.
   7. Inspect A/C condenser for airflow restrictions; determine necessary action.
   8. Remove, inspect, and reinstall receiver/drier or accumulator/drier; determine recommended oil quantity.
   9. Remove, inspect, and install expansion valve or orifice (expansion) tube.
   10. Inspect evaporator housing water drain; perform necessary action.
3. Complete Level 2 NATEF tasks related to Heating, Ventilation, and Engine Cooling Systems Diagnosis and Repair.
   1. Inspect engine cooling and heater systems hoses; perform necessary action.
   2. Inspect and test heater control valve(s); perform necessary action.
4. Complete Level 2 NATEF tasks related to Operating Systems and Related Controls Diagnosis and Repair.
   1. Inspect and test A/C-heater blower motors, resistors, switches, relays, wiring, and protection devices; perform necessary action.
   2. Diagnose A/C compressor clutch control systems; determine necessary action.
   3. Diagnose malfunctions in the vacuum, mechanical, and electrical components and controls of the heating, ventilation, and A/C (HVAC) system; determine necessary action.
   4. Inspect and test A/C-heater control panel assembly; determine necessary action.
   5. Inspect and test A/C-heater control cables, motors, and linkages; perform necessary action.
   6. Inspect A/C-heater ducts, doors, hoses, cabin filters, and outlets; perform necessary action.
   7. Identify the source of A/C system odors.
   8. Check operation of automatic or semi-automatic heating, ventilation, and air-conditioning (HVAC) control systems; determine necessary action.
5. Complete Level 2 NATEF tasks related to Refrigerant Recovery, Recycling, and Handling.
   1. Perform correct use and maintenance of refrigerant handling equipment according to equipment manufacturer's standards.
   2. Identify and recover A/C system refrigerant.
   3. Recycle, label, and store refrigerant.
   4. Evacuate and charge A/C system; add refrigerant oil as required.