LG LMC1575BD Service Manual page 44

4. F-19 Inverter PCB Check
LMC1575BD /01
LMC1575ST /01
LMC1575SW /01
LMC1575SB /01
※ Tester mode : Beep mode
• Check D5 (Bridge Diode), D8 / D9 (High Voltage Diode)
Status Test result
Normal Open (OL)
Abnormal Short (Beep)
+ ~ ~ -
D8
D9
Example : abnormal
Bridge Diode : AC Checking Bridge Diode : DC Checking HVD : D8, D9 Short Checking
(Short)
Example : normal
(Open)
• Check Q1 (IGBT)
※ Tester mode : Diode mode
※ Tester mode : Beep mode or resistor mode
Status Test result
Status Test result
Normal 0.4V ↑(about 0.4 ~
Normal About 10Kohm
0.6V)
Abnormal 10Kohm ↓ or short
Abnormal 0.4V ↓ or short
Example : abnormal
Example : normal
C
Refer to Check point
Example : abnormal
(Short)
Example : normal (Short)
G E
5-32