LG LMNH122LRA0 Service Manual page 114

Troubleshooting Guide
1) Troubleshooting CH01, CH02, CH06
Display
Title
code
Indoor air sensor
01
Indoor inlet pipe sensor
02
06
Indoor outlet pipe sensor
Check Point
1. Unplug the sensor on Indoor unit PCB.
2. Estimate the resistance of each sensor.
3. If the resistance of the sensor is 10KΩ/ 5KΩ at 25°C, then sensor is normal.
4. If the resistance of the sensor is 0 KΩ or ∞, then sensor is abnormal.
5. Plug the sensor on Indoor unit PCB and Power ON.
6. Estimate the voltage of each sensor.
7. If the voltage of the sensor is 2.5Vdc at 25°C, then sensor is normal.
8. If the resistance of the sensor is 0 or 5Vdc, then sensor is abnormal.
114 Multi type Air Conditioner
Cause of error
• Open / Short
• Soldered poorly
• Internal circuit error
• Open / Short
• Soldered poorly
• Internal circuit error
• Open / Short
• Soldered poorly
• Internal circuit error
Ω
10k
Ω
Check the resistance
Check point & Normal condition
Normal resistor : 10KΩ/ at 25°C (Unplugged)
Normal voltage : 2.5Vdc / at 25°C (plugged)
Normal resistor : 5KΩ/ at 25°C (Unplugged)
Normal voltage : 2.5Vdc / at 25°C (plugged)
Normal resistor : 5KΩ/ at 25°C (Unplugged)
Normal voltage : 2.5Vdc / at 25°C (plugged)
2.5Vdc
V
Check the voltage
Change the sensor.
Repair or Change the PCB.