Samsung AM072/096/120/144FXVAFH, Service Manual

Page: 131 / 295

Troubleshooting
4-34 Samsung Electronics
4-4-6 Internal Communication error of the Outdoor Unit C-Box
Outdoor unit display
- All boards of outdoor unit are not communicating
Indoorunit display
Duct, Cassette (1/2 Way),Console, Celing Cassette (4/Mini4 Way) Wall-mounted (NeoForte)
Operation Defrost Timer Fan Filter/MPI Operation Defrost Timer Filter Operation Timer Turbo
× × ◑ ◑
×
× ◑ ◑ × × ◑ ◑
※ ● : ON ◑ : Flash × : OFF
Judgment Method ∙ Communication error between the C-Box PCB
Cause of problem
∙ Communication wire inside the C-Box is unconnected
∙ Main PCB defective
1. How to check
Replace Main PCB
Restart operation after connecting the Inverter
PCB2 CN31(when the Comp. applied one :
Inverter PCB1) connector. (Check the 3, 4 Pin short)
* Service after turn off the Main Power.
No
Yes
Is the jumper connector connected to
CN31 of Inverter PCB2(when the Comp. applied
one : Inverter PCB1)?
Restart operation after checking the Inverter
PCB2 CN31 and PCB2 CN32 Communication
wire/Connector.(3, 4 Pin Short)
* Service after turn off the Main Power.
No
Yes
Yes
Is Inverter PCB1 CN32 and Inverter PCB2
CN31 connector accurately connected?
1) Check the Inverter PCB1 CN32, CN91 and
Fan PCB CN12 Communication wire/
Connector.
2) Restart operation after connecting the Hub
PCB CN97 and Fan PCB CN13 connector.
* Service after turn off the Main Power.
1) Check the Main PCB : Main PCB TX circuit
inspection
2) Check the Hub PCB : Hub PCB TX circuit
inspection
* Service after turn off the Main Power.
No
No
Yes
Is Inverter
PCB1 CN32 and Fan PCB CN12 connector
accurately connected?
Does FAN PCB LD22/LD32 (LED) blink?
Two Comp. applied to the model