Samsung AC071MN4PKH Service Manual page 78

Troubleshooting
Indoor/outdoor communication error (1 min.) (Error Code: E202) (cont.)
Continue
Check the communication circuit of the Main PCB of the outdoor unit.
1. Is there a fault in communication IC?
2. Is there a fault in TVS-Diode?
Measuring Communication IC Measuring Part
Part
Location
Measuring #5-GND, #6- Communication A, #7-
Point
Communication IC Measuring (Port)
#6 - #5
#7 - #5
#8 - #5
TVS-Diode Measuring
Both ends of diode
Yes
(Circuit Diagram)
Communication B, #8-Vcc
Steady-state Measuring Value
Steady-state Measuring Value
Example of Measuring
Communication IC
COM 1(RED)
0.9kΩ ~ 1.2kΩ
0.9kΩ ~ 1.2kΩ
4.7Vdc ~ 5.3Vdc
1kΩ or above
4-38
Example of Measuring
TVS-Diode
Remark
Measuring after separating the
communicatio
connection