Troubleshooting
Samsung Electronics
4-23
※
Essential Requirements before PCB Changes in Case of Communication Error Occurrence
1. Find the communication IC near the communication terminal.
●
Indoor Unit
- Coil side or PTC (SMD) side : Communication IC between indoor and outdoor units.
●
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 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. Defectiveness decision of the communication IC which uses a measurement resistance value.
●
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.
●
Judging as defective
- One or both are low with tens of Ω
- One or both of them is open
Indoor Unit
Outdoor Unit
Outdoor unit
communication between
Indoor Unit communication
Transmitter communication
No.5
No.6
No.7
