LG A2UQ166FA0, Service Manual, Page: 182 / 238

182 Multi type Air Conditioner
5) Troubleshooting CH21
Ω
Comp
Copper
pipe
Resistance(
Ω
) at 20°C
Resistance(
Ω
) at 20
°
C
0.64
0.64
0.64
Inverter
comp.
V-W
W-U
U-V
Terminal
0.8
0.8
0.8
Constant
comp.
2M
Ω
2M
Ω
2M
Ω
Inverter
comp.
V-GND
W-GND
U-GND
Terminal
2M
Ω
2M
Ω
2M
Ω
Constant
comp.
V
U
W
Ω
Comp
21
DC Peak
• Instant over current
• Over Rated current
• Poor insulation of IPM
• An instant over current in the U,V,W phase
- Comp lock
- The abnormal connection of U,V,W
• Over load condition
- Overcharging of refrigerant
- Pipe length.
• Poor insulation of compressor
Display
code
Title Cause of error Check point & Normal condition
Check Point
1. Check the wire connection. (U,V,W)
2. Check the load condition. (Refrigerant, Pipe length, …)
→
Adjust the load condition
3. Check the electricity leakage of the compressor.
→
Normal : Over 2M
Ω
.
4. Check the resistance of compressor.
→
Normal : 0.65
Ω
(INV), 0.8
Ω
(Cons.)
→
No difference at each terminal.
5. Check the insulation from water at IPM part.
→
Check the trace of water.
6. Check the IPM circuit.
Troubleshooting Guide