Samsung AQ12A5(6)MB Service Manual page 21

Troubleshooting
5-2-3 When the Outdoor Unit Does Not Operate. (Initial Diagnosis)
1) Checklist :
(1) Is input voltage normal?
(2) Is the set temperature of the remote control higher than room temperature in COOL mode?
(3) Is the POWER IN connector (CN71) linked correctly?
(4) Is the outdoor unit properly connected with the TERMINAL BLOCK connector((N1), 1)?
2) Troubleshooting procedure
After unplugging out the power cord should be
reconnected within five seconds.
Does the STD lamp blink
Does the timer lamp blink during operation ?
Is the power relay RY71 operated by adjusting the room
temperature?
Test rod location
+ -
IC4 Pin No.62 GND
Is rating voltage ±10% range applied relay between Terminal block
NO(N1) and No. 1
5-4
NO
YES
YES
NO
3
NO
Normal
Condition Voltage
RY71 ON DC 4.8V
NO
YES
1
YES
Is the room sensor normal register?
10°C
17.96k Ω
Check as in the procedure "No Power parts"
1
Room temperature sensor is
out of order
2
Microcomputer is
out of order.
Power relay is
out of order
Outdoor unit is
out of order.
NO
2
20°C 30°C
12.09k Ω 8.3k Ω
YES
3
Refer to page 5-2.
PCB should be checked.
PCB should be
checked.
Power relay should be
replaced.
Samsung Electronics