External Pcb - LG MULTI V 5 Manual Book

13.2 Failure Cause
1. High voltage (T-N more than 484V, N phase wiring fault) → CH50
2. Rainwater inflow by Control box / Front Panel / Service port open, Control box screw loosening
3. Part short by foreign substance
4. Defective PCB / Diode / Resistance / Capacitor / Regulator
13.3 Precautions of Replacement
1. Be sure to use the main PCB suitable for the model (Check P/No)
2. Be sure to turn off the power and wear insulated gloves before touching the PCB.
3. Use box or bag only for PCB.
4. If on-boarding is required after replacement, check the program and EEPROM C/Sum (especially when
using an alternate Main PCB)
13.3 Check Point after Replacement
1. Check whether there is any abnormality when the cycle is stabilized at cooling or heating mode.
2. Check current Hz control according to target Hz
3. Check that the target high / low pressure is reached
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14. External PCB

14.1 Failure Judge Method
1. Error code check
Error Code
16. External PCBA
CH05, CH53, CH104, · Even after checking the connection condition of indoor and outdoor
CH237, CH238 communication lines (shield wire, unshield wire)
CH32, CH33, CH34,
1.1 불량 판단 방법
CH35, CH36, CH41,
CH42, CH43, CH44,
· Even after replace each temperature sensor, pressure sensor, and
에러 코드
CH45, CH46, CH47,
valve replacement.
CH113,
CH114, CH115, CH116,
CH05, CH32, CH33, CH34, CH35, CH41, CH42,
CH151, CH153, CH154
CH43, CH44, CH45, CH46, CH47, CH53, CH104,
· Even after checking Main - External PCB communication
CH145
CH113, CH114, CH115, CH116, CH145, CH151, harness(6pin, Blue) connection condition
CH153, CH154, CH237, CH238
2. External PCB check
Commu-
On-boarding
Power
DDC
ACT_
Reserved
OIL 2
ACT_ Active
OIL 1 Path
Receiver Receiver
MICOM
Out In
HEX HEX
High Low
IN J OIL_
Suction BAL_V1
4way2 4way1
Accum IN V2
Oil Heater
IN V1
Heater
ODU.IDU.Dry contact
IN V2
P/SW IN V1
삭제 V
AC Load
Dohug
Comm. Connetor
ID U.B ID U.A DRY.1 DRY.1 GND 12V
1.2 주요 불량 원인
· 고전압 인가 (T-N 494 V 이상, N상 오결선 시 CH50 발생)
Error diagnosis
• 실내외기간 통신선(실드선
CH237, CH238)
• 각 온도센서, 압력 센서, 밸
CH42, CH43, CH44, CH4
• Main-External간 연결 통신
Cycle
Digital
nication Sensor
Main
Reserved
EEV1
EEV 삭제
Main
EEV2
SC
EEV
D VI
EEV
VI
EEV1
VI
EEV2
Reserved1
Snow
Air Temp.
Sensor
Reserved2
Humidity
Liquid Pipe Temp.
Sensor
Heat Exchanger Upper
Oil Level Low Pressure
SC Discharge
IN V1 Sensor
IN V1 Discharge
High Pressure
Heat Exchanger
Sensor
Suction Temp.
Heat Exchanger Lower
SC Suction
Oil Level
IN V2 IN V2 Discharge
D VI Suction
D VI Discharge
Temp./Pres-
sure Sensor
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