Johnson Controls CICM008B21S, Service Manual

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3-18
SM-18003
TROUBLESHOOTING
3.2.2 Troubleshooting Using Alarm Codes
l
The RUN indicator (red) flashes.
l
The indoor unit number (refrigerant cycle number - address number), the alarm code, the model code
1
,
the model name
1
and the number of connected indoor units are displayed on the LCD. The indoor unit
number and the alarm code are displayed on the 7-segment display of the outdoor unit PCB.
Note 1: Except for some models.
This alarm code is displayed when the contact between #1 and #2 of CN14 on the I.U. PCB is opened for
over 120 seconds during the cooling, dry, fan, or heating operation.
I.U. PCB: Indoor Unit PCB
Turn OFF power supply and remove
connectors CN36 and CN14 on I.U. PCB.
Then turn ON power supply. Is DC12.5~
13.5V applied between CN36 terminals?
Turn OFF power supply and connect
connector CN14 on I.U. PCB. Then
turn ON power supply. Is voltage applied
between CN36 terminals less than 12.5V?
Failure of I.U. PCB
Failure of Drain Pump
Activation of Float Switch FS
or Failure of Float Switch.
Yes
Make sure short circuit does not occur between CN36 terminals
when measuring the voltage. Short circuit will lead to I.U. PCB
malfunction.
Yes
No
No
Indication on Outdoor Unit PCB
Unit No.
of Malfunctioning Indoor Unit
Alarm Code
Alarm
Code
Activation of Protection Device (Float Switch) in Indoor Unit