1. Poor Cooling

• Check A/C button activation

• Inspect compressor belt tension

• Test refrigerant pressure (recharge R134a if <2bar)

2. Low Airflow

• Clean/replace AC filter

• Test fan speed module (replace variable resistor if no speed change)

3. Engine Stalling with AC On

• Verify engine power (≥90% rated)

• Clean air/fuel filters

• Check compressor clutch for slipping

4. Air Duct Blockage

• Flush evaporator fins

• Re-vacuum and recharge refrigerant

• Disinfect ducts every 500h

5. No Cooling (Common Missteps)

• Confirm A/C light is on

• Check fuse (cab F12)

• Set temperature 5℃ below ambient

Maintenance Tips

1. Clean condenser fins every 200h

2. Inspect refrigerant via sight glass before summer

3. Prioritize relay & temperature sensor checks