MX-M850 (serv.man38). Section 8 Self Diagnostics Trouble Codes - Sharp Copying Equipment Service Manual (repair manual). Page 19

MX-M1100 SELF DIAG AND TROUBLE CODE  8 – 19

 

 

 

 

 

 

 

 

 

Detail

Toner control sensor output open

Section

PCU

Cause

Connector and harness trouble.
Connector not connected.
Developer empty, or abnormally little developer.
Sensor abnormality.

Check & 
Remedy

Check connection of the harness of the toner control 
sensor. 
Check connection of the interface harness on the rear 
side of the developer tank. 
Check connection of the connector and the harness to 
the main PWB. 
Check for disconnection of the harness. 
If the trouble is not canceled, replace the sensor, or 
replace the developing unit. 

Detail

Toner end though the remaining quantity is not 0%.
The count value of the toner cartridge motor rotation 
sensor exceeds the level 3 times greater than the 
specified level.

Section

PCU

Cause

Toner motor section connector harness trouble.
Toner motor and toner density sensor trouble.

Check & 
Remedy

Check connection of the connector in the toner motor 
section.  
Check connection of the connector harness (TM) to the 
main PWB.  
Check the output of the toner density sensor (SIM 25-1).
Replace the toner cartridge (CRUM). 
If the trouble still remains after replacement of the toner 
cartridge (CRUM), check the developing unit. 

Detail

Improper data are found in the CRUM content when 
detection the normal CRUM of the cartridge

Section

PCU

Cause

An improper cartridge is inserted. 
Toner cartridge trouble.

Check & 
Remedy

Replace the toner cartridge.

Detail

Read/write operation of the CRUM cannot be performed

Section

PCU

Cause

CRUM trouble.
Contact trouble or disconnection of the connector and 
the harness between the PCU and the toner cartridge.  
Control PWB (PCU) trouble.

Check & 
Remedy

Replace the toner cartridge. 
Check the connector and the harness between the PCU 
and the toner cartridge. 
Replace the PCU PWB. 

Detail

Installed CRUMID trouble

Section

PCU

Cause

An improper cartridge is inserted. 
Toner cartridge trouble.

Check & 
Remedy

Replace the toner cartridge.

Detail

Density sensor harness open or short, sensor detection 
trouble

Section

PCU

Cause

Density sensor dirt, density sensor trouble.
Density sensor harness connection trouble.
PCU PWB Trouble. Drum surface state abnormality. 
Drum charging state abnormality.

Check & 
Remedy

Check connection of the harness and the connector of 
the sensor. 
Check the PCU PWB. Check for dirt on the sensor 
section. Clean or replace as needed. 
Check the drum surface condition. Use Sim. 44-2 to 
check the operation. Execute DARK V0 of Sim. Sim. 44-
3 to check the operation. 

Detail

Front surface potential sensor open or short, sensor 
detection trouble

Section

PCU

Cause

Sensor dirt, sensor trouble.
Surface potential sensor harness connection trouble.
PCU PWB Trouble. Drum surface state abnormality. 
Grid high voltage output trouble. 
Drum charging abnormality due to dirt on the MC grid. 
The drum life is reached. 

Check & 
Remedy

Check connection of the harness and the connector of 
the sensor. 
Check the PCU PWB. Check for dirt on the MC grid. 
Clean or replace as needed. 
Check the drum surface condition. Use Sim. 22-1 to 
check the drum life meter. If it is 100%, it means that the 
drum life is reached, and maintenance must be 
performed. 
Use Sim. 44-3 to execute DARK V0 and check the 
operation. 
Check the grid high voltage output. 

Detail

Process thermistor open

Section

PCU

Cause

Process thermistor trouble.
Process thermistor harness connection trouble.
PCU PWB trouble.

Check & 
Remedy

Check connection of the harness and the connector in 
the process thermistor. 
Check the PCU PWB. 

Detail

Room temperature  thermistor open or short

Section

PCU

Cause

Room temperature thermistor trouble, room 
temperature thermistor harness connection trouble, 
PCU PWB trouble.

Check & 
Remedy

Check connection of the room temperature harness /
connector. Check the PCU PWB.