12-4
TROUBLESHOOTING
SM PNXDCI 1-A.1 GB
12.3.2
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
