Troubleshooting for MSP Duct Type Indoor Unit
SiSG121917E
127
Part 6 Service Diagnosis
6. Troubleshooting for MSP Duct Type Indoor Unit
6.1 Indoor Unit PCB Abnormality
Error Code
A1
Method of Error
Detection
The system checks the data from EEPROM.
Error Decision
Conditions
When the data from the EEPROM is not received correctly
EEPROM (Electrically Erasable Programmable Read Only Memory): A memory chip that holds
its content without power. It can be erased, either within the computer or externally and usually
requires more voltage for erasure than the 5 volts used in logic circuits. It functions
like non-volatile RAM, but writing to EEPROM is slower than writing to RAM.
Supposed
Causes
Defective indoor unit PCB
External factor (noise etc.)
Troubleshooting
Caution
Be s
u
re to t
u
rn off the po
w
er s
w
itch
b
efore connecting or disconnecting
connectors, or parts may
b
e damaged.
(R22247)
N
ormal?
T
u
rn off the po
w
er. Then, t
u
rn on
the po
w
er to restart the system.
N
O
YES
External factor other than malf
u
nction
(for example, noise etc.)
Replace the indoor
u
nit PCB
(control PCB).
