Samsung AM072FXVAFH series Service Manual page 186

Troubleshooting
IPM breakdown diagnostics (FAN PCB)
1. Preparations before checking
1) Power Off
2) IPM failure, discharge mode may not work properly. Therefore, wait more than 15 minutes after the Power Off.
3) Remove all of the Fan PCB connectors. (Comp connector included)
4) Prepare the digital multi tester.
2. Inspection Method
1) Refer to Figure1 and Table1, respectively the resistance value and diode voltage value measure.
2) According to the criterion in Table 1 to determine whether the failure of IPM.
Division
Measure
the resistance values
Measure the diode
voltage values
4-90
Measured Point
Criterion
+ -
40 U
40 V
40 W
More than
500
U 34
V 34
W 34
U 40
V 40
W 40
0.3~0.7V
34 U
34 V
34 W
< Table 1 >
Remark
Measurement error can occur for reasons
such as the initial measurement condenser
discharge.
Measured over at least three times.
< Figure 1 >
Fan PCB
Samsung Electronics