AR-M550 (serv.man16). (9) Self diag message and troubleshooting - Sharp Copying Equipment Service Manual (repair manual). Page 30

AR-M550/M620  SELF DIAG MESSAGE AND TROUBLESHOOTING  9 - 30

Main 
code

Sub 

code

Title

Phenomenon

Display

Lamp
Message

Details

Fusing section high 
temperature trouble
The fusing temperature 
exceeds 241.5°C. (An 
input voltage of 0.35V or 
less is detected.)
When fusing temperature 
control is started and a 
temperature of 242°C is 
detected 3 times 
continuously in sampling 
of 100 (150) msec 
interval. (Except for 
Japan)

Section

Engine

Operation 
mode

Note 

Case 1

Trouble 
position/
Cause

Thermistor trouble
Control PWB trouble
Improper connection of 
the fusing section 
connector
AC power trouble

Remedy

Use SIM 5-2 to check 
flashing of the heater 
lamp.
When the lamp flashes 
normally.
• Check the thermistor 

and the harness.

• Check the thermistor 

input circuit on the 
control PWB.

When the lamp keeps 
ON.
• Check the AC PWB 

and the lamp control 
circuit on the control 
PWB.

Use SIM 14 to cancel the 
trouble

Note 

Main 
code

Sub 

code

Title

Phenomenon

Display

Lamp
Message

Details

Fusing section low 
temperature trouble
The set temperature is 
not reached within the 
specified time (normally 4 
min) after turning on the 
power relay.
The heater lamp does not 
turn off in 4 min after 
starting warming up.
After completion of 
warming up, a 
temperature of 80°C is 
detected 5 times 
continuously in sampling 
of 100 (150) msec 
interval. (Except for 
Japan)

Section

Engine

Operation 
mode
Note 

Case 1

Trouble 
position/
Cause

Thermistor trouble
Heater lamp trouble
Control PWB trouble
Thermostat trouble
AC power trouble
Interlock switch

Remedy

Use SIM 5-2 to check 
flashing of the heater 
lamp.
When the lamp flashes 
normally.
• Check the thermistor 

and the harness.

• Check the thermistor 

input circuit on the 
control PWB.

When the lamp does not 
turn on.
• Check for 

disconnection of the 
heater lamp or the 
thermostat.

• Check the interlock 

switch.

• Check the AC PWB 

and the lamp control 
circuit on the control 
PWB.

Use SIM 14 to cancel the 
trouble

Note