Samsung AVXCSH022EE Service Manual page 171

❈ Essential Requirements before PCB Changes in Case of Communication Error Occurrence
1. Find the communication IC near the communication terminal.
● Indoor Unit
Above Red Connector: Communication IC between indoor and outdoor units
Above Blue Connector: Communication IC for cable remote control
● Outdoor Unit
When there is module communication as in PLUS II and PLUS III – Above Red Connector of Main Unit: Communication IC between
indoor and outdoor units
When there is no module communication as in PLUS II and PLUS III – Above Yellow Connector of Each Unit: Communication IC
between outdoor units
Other Outdoor Unit- Above Communication Connector: Communication IC between indoor and outdoor units
Indoor Unit
2. Measure the resistance of the communication IC.
● Measurement Method: Measure the No. 5-No.6 Pin resistance
Measure the No. 5 – No.7 Pin resistance
3. Both lights are tested for communication IC by using measured resistance.
● Judging as Normal
- Each resistance value should be measured in tens of kΩ~to hundreds of kΩ.
- Difference between the two resistance values should be of some number of kΩ.
● Criteria for Problem
- One or both are low with tens of Ω
- One or both of them is open
Samsung Electronics
Module-type Outdoor Unit
Troubleshooting
Solo-type Outdoor Unit
Display IC No. 1 pin
No. 5 No. 6 No. 7
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