MX-1800N (serv.man16). Section 8 - Self Diagnostics Trouble Codes - Sharp Copying Equipment Service Manual (repair manual). Page 14

MX-1800N  SELF DIAG AND TROUBLE CODE  8 – 14

 

 

 

 

 

 

Trouble content

Toner empty sensor output abnormality. Sample 
level 25 or less or 231 or above.

Section

PCU

Case 1

Cause

The connector is not installed.

Check and 
remedy

Check the connection of the connector harness to 
the PCU PWB. Check the connection of the toner 
empty sensor. 

Case 2

Cause

Connector harness trouble

Check and 
remedy

Check the harness disconnection.

Case 3

Cause

Cartridge trouble

Check and 
remedy

Check the cartridge connection.

Trouble content

Toner empty sensor output abnormality. Sample 
level 25 or less or 231 or above.

Section

PCU

Case 1

Cause

The connector is not installed.

Check and 
remedy

Check the connection of the connector harness to 
the PCU PWB. Check the connection of the toner 
empty sensor. 

Case 2

Cause

Connector harness trouble

Check and 
remedy

Check the harness disconnection.

Case 3

Cause

Cartridge trouble

Check and 
remedy

Check the cartridge connection.

Trouble content

The transfer belt surface is scanned by the image 
density sensor before starting the process control, 
and adjust the sensor gain so that the output is 
kept at a certain level. However, the output is not 
within the specified range though the senor gain is 
adjusted.

Section

PCU

Case 1

Cause

Image density sensor trouble, harness connection 
trouble between PCU PWB and the image density 
sensor, image density sensor dirt, transfer belt 
cleaning trouble, calibration plate solenoid 
operation trouble

Check and 
remedy

Use SIM44-2 to execute the process control 
sensor gain adjustment. If "ERROR" is displayed, 
check the sensor, the  harness, the calibration 
plate solenoid operation for any trouble. If the 
adjustment is completed, check the transfer belt 
surface state. 

Trouble content

The calibration plate surface is scanned by the 
image density sensor before starting the process 
control, and adjust the sensor gain so that the 
output is kept at a certain level. However, the 
output is not within the certain level though the 
senor gain is adjusted.

Section

PCU

Case 1

Cause

Image density sensor trouble, harness connection 
trouble between PCU PWB and the image density 
sensor, image density sensor dirt, calibration plate 
dirt, calibration plate solenoid operation trouble

Check and 
remedy

Use SIM44-2 to execute the process control gain 
adjustment. If "ERROR" is displayed, check the 
sensor and the  harness. If the adjustment is 
completed, check the calibration plate solenoid 
operation.

Trouble content

The detection temperature is out of the range of 
–28

°C to 78°C.

Section

PCU

Case 1

Cause

LSU thermistor harness connection trouble

Check and 
remedy

Check the connection of the LSU thermistor 
harness and connector.
If the trouble cannot be removed, replace the LSU 
thermistor or the PCU PWB.

Case 2

Cause

LSU thermistor trouble, PCU PWB trouble

Check and 
remedy

Check the PCU PWB.
If the trouble cannot be removed, replace the LSU 
thermistor or the PCU PWB.

Trouble content

Detection is made by interruption of light in the 
sensor section of the projection rib on the drum 
drive gear to control the BK drum phase. The 
detection signal cannot be acquired and phase 
control cannot be made.

Section

PCU

Case 1

Cause

Sensor connector connection trouble

Check and 
remedy

Check the sensor connector connection.

Case 2

Cause

Dirt on the sensor light emitting section, or 
installation trouble

Check and 
remedy

Check for dirt on the sensor or check the 
installation state. 

Case 3

Cause

Drum drive gear upper rib breakage, sensor 
trouble

Check and 
remedy

If there is no trouble in the rib, replace the sensor. 
(Use SIM30-1 "DHPD_K" to check interruption or 
transmission of light.)