MXS Service Manual

SiUS121736EA Troubleshooting with LED
Service Diagnosis 136
Caution: When operation stops suddenly and the operation lamp blinks, it could be operation mode conflict.
For FFQ models, even if the operation mode conflict occurs, the operation lamp does not blink.
1) Check if the operation modes are all the same for the indoor units connected to multi system
outdoor unit?
2) If not, set all the indoor units to the same operation mode and confirm that the operation lamp is
not blinking.
3) Moreover, when the operation mode is automatic, set all the indoor unit operation mode as
cooling or heating and check again if the operation lamp is normal.
If the lamp stops blinking after the above steps, there is no malfunction.
∗Operation stops and operation lamp blinks only for the indoor unit that has a different operation
mode set later. (The first set operation mode has priority.)
Service Monitor The indoor unit has a green LED (LED A or HAP) on the control PCB. When the microcomputer
works in order, the LED blinks. (Refer to pages 26, 28, 30, 32, 34, 36, 38 for the location of LED.)
2.2 Outdoor Unit
The outdoor unit has a green LED (LED A) and red LEDs (LED 1 ~ LED 5) on the PCB.
When the microcomputer works in order, the LED A blinks, and when the system is in normal
condition, the red LEDs are OFF.
Even after the error is canceled and the unit operates in normal condition, the LED indication
remains.
(R23944)
A
1
2
3
4
5
LED A
LED 1
LED 2
LED 3
LED 4
LED 5
Service monitor PCB