LG MULTI V M ARNU07GTU 4 Series Svc Manual page 44

Checking Method for Key Components
• EEV failure check method
Failure mode
Microcomputer 1.Disconnect the EEV connector form control board and
Driving circuit connect testing LED
failure
2. Main power ON, pulse signal is out from EEV for 17 s
If LEDs do not turn on, or are in on state continuously,
then driving circuit is abnormal
EEV locking 1.If EEV is locked, in no load state, the driving motor rotate,
and clicking sound always occurs
EEV Motor coil 1. Check the resistance between coil terminal
short or (red-white, red-yellow, red-orange, red-blue)
misconnection 2. If the estimated resistance value is in 52±3
then the EEV is normal
1. Check the resistance between coil terminal
(brown-white, brown-yellow, brown-orange, brown-blue)
2. If the estimated resistance value is in 150±10
then the EEV is normal
Full closing 1. Operate indoor unit with FAN mode and operate another
(valve leakage) indoor unit with COOLING mode
2. Check indoor unit(FAN mode) liquid pipe temperature
(from operation monitor of Compressor Module control board)
3. When fan rotate and EEV is fully closed, if there is any
leakage, then the temperature is down
If estimated temperature is very low in comparison with
suction temperature which is displayed at remote
controller then the valve is not fully closed
Diagnosis
1KΩ LED
- 44 -
Repair process
Check and replace
Indoor unit control
board
Replace EEV
Replace EEV
Replace EEV
If the amount of
leakage is much,
Replace EEV
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Only training and service purposes.
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MULTI V M
Indoor
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Indoor
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