Panasonic U-72MF2U9 Service Manual page 169

3. 3WAY Alarm Codes
E06 Alarm
Alarm code E06
Alarm meaning Some indoor units does not respond to outdoor unit.
Alarm conditions Some indoor units does not respond to outdoor unit.
Probable cause (1) The indoor unit power was cut OFF after initial communications were completed.
(2) An open circuit or short-circuit occurred in the inter-unit control wiring after initial
communications were completed.
Check Check the power at the indoor and outdoor units, and check the inter-unit control wiring.
Correction —
Example —
Notes This alarm is detected after initial communications are completed. Therefore, it does not occur in
cases of "disconnected serial connector," "no terminal unit set," or other trouble that occurs
before initial communications are completed. If initial communications have not been completed,
alarm E04 occurs.
E12 Alarm
Alarm code E12
Alarm meaning Auto Address failed to start.
Alarm conditions Auto address setting was started when auto address setting was in progress at another outdoor
unit in the same link.
Probable cause Auto address setting is in progress at another outdoor unit.
Check This alarm is not displayed on the remote controller. Therefore check the blinking on the Outdoor
Unit Control PCB.
Correction Wait for auto address setting to be completed at the outdoor unit where it is currently in progress.
Then start auto address setting again.
Example —
Notes —
E15 Alarm
Alarm code E15
Alarm meaning Fewer indoor units are found in Auto Addressing than the setting on outdoor PCB.
Alarm conditions The number of indoor units was too few when auto address setting was performed.
Probable cause (1) The number of indoor units set at the indoor unit quantity setting SW (SW3, SW4) on the
Outdoor Unit Control PCB is too many.
(2) The inter-unit control wiring between indoor units has been cut.
Check (1) See the section "6. TEST RUN" and check the indoor unit quantity setting SW (SW3, SW4).
(2) Check the inter-unit control wiring at the indoor and outdoor units.
Correction After correcting the indoor unit quantity setting or the inter-unit control wiring, perform auto
address setting again.
Example —
Notes 3WAY switch position
5 - 7
3WAY VRF SYSTEM
Trouble Diagnosis
SW4
SW3
1
2
3
4
5
6
7
8
9