Service manual

11-4
TROUBLESHOOTING
SM SX DCI 1-A.3 GB
No Problem AO54321
28 Model A No 1 1 1 0 0
29 Model B No 1 1 1 0 1
30 Model C No 1 1 1 1 0
31 Model D No 1 1 1 1 1
* CN / LSN Units only
11.3.2 Indoor Unit Diagnostics and Corrective Actions
No. Fault Probable Cause Corrective Action
1
Sensor failures
of all types
Check sensor connections or
replace sensor
2
Communication
mismatch
Indoor and Outdoor
controllers are with
different versions
Replace Indoor controller
3
No
Communication
Communication or
grounding wiring is not
good.
Check Indoor to Outdoor
wiring and grounding
4 No Encoder
Indoor electronics or
motor
Check motor wiring, if ok,
replace motor, if still not ok,
replace Indoor controller.
5
Outdoor Unit
Fault
Outdoor controller
problem
Switch to Outdoor
diagnostics.
6
EEPROM Not
Updated
System is using ROM
parameters and not
EEPROM parameters
No action, unless special
parameters are required for
unit operation.
7 Bad EEPROM
No action, unless special
parameters are required for
unit operation.
8
Bad
Communication
Communication quality
is low reliability
Check Indoor to Outdoor
wiring and grounding
9
Using EEPROM
data
No problem. System is
using EEPRRRROM
parameters
11.3.3 Outdoor Unit Diagnostics
The outdoor alarm outputs are defined in the following way:
No Problem AO 5 4 3 2 1
1 OCT is disconnected Yes 0 0 0 0 1
2 OCT is shorted Yes 0 0 0 1 0
3 CTT is disconnected Yes 0 0 0 1 1
4 CTT is shorted Yes 0 0 1 0 0
5 HST is disconnected (when enabled) Yes 0 0 1 0 1
6 HST is shorted (when enabled) Yes 0 0 1 1 0
7 OAT is disconnected (when enabled) Yes 0 0 1 1 1
8 OAT is shorted (when enabled) Yes 0 1 0 0 0
9 OMT is disconnected (DCI72 / 72Z / 80) Yes 0 1 0 0 1
CONTENT