35
Chapter 6.  Maintenance and Inspection
Alarm codes and details
If a fault stop occurs, the alarm code and the code for the operating status where the 
fault stop occurred are displayed alternately.
Alarm 
code
Sub-
code
Description Status Cancellation method
E9 08
Alarm at power-on When the cause of the fault stop cannot be identified
• Device power was turned off before the cause of 
the error was saved.
• The internal latch relay was set due to 
transportation vibration, etc.
This does not indicate a problem with the device.  
Reset the device to restore normal operation.
Reset
E9 50
Internal error ROM 
checksum
ROM check code error Reset
E9 5 1
Internal error EEPROM 
read
Error in reading from the EEPROM
• Data was not correctly saved to the EEPROM with 
the Smart Loader Package (SLP-A55) because the 
power was turned OFF or the loader cable was 
removed while settings were being written, etc.
• Due to some other failure of the EEPROM, data was 
not correctly saved.
 What to do if E951 
occurs (p.36)
E9 52
Internal error EEPROM 
write
Error while writing to the EEPROM Reset
E9 53
Internal error process 
data value
Internal memory error Reset
E9 54
System error (1) CPU communication error Reset
E9 55
Internal error  
(input-circuit)
Detection of part failure (voltage applied to the 
input terminals by wrong wiring) or strong inductive 
electrical noise to the signal wire
Reset
E9 56
Internal error  
(input-circuit) 
Internal clock error Reset
E9 57
Internal error  
(EEPROM data value)
An error was found in CPU mutual check.
There are discrepancies in EEPROM data.
Reset
E9 58
Internal error  
(CPU mutual check)
An error was found in the CPU internal status mutual 
check.
Reset
E9 60
Internal error  
(CPU mutual check)
An error was found in the CPU process status mutual 
check.
Reset
E9 6 1
Internal error  
(CPU mutual check)
CPU process synchronization error Reset
E9 63
Internal error  
(CPU mutual check)
Internal memory data error
• While settings were being written with the Smart 
Loader Package (SLP-A55), the power was turned 
OFF or the loader cable was removed.
Write settings using the 
Smart Loader Package 
(SLP-A55), and then do 
a reset.
E9 64
Internal error  
(flame circuit)
Error in the circuit for diagnosing the flame detection 
circuit
Reset
E9 65
Internal error  
(flame circuit)
Error in the interactive diagnosis of the flame 
detection circuit
Reset