AR-M550 (serv.man16). (9) Self diag message and troubleshooting - Sharp Copying Equipment Service Manual (repair manual). Page 10

AR-M550/M620  SELF DIAG MESSAGE AND TROUBLESHOOTING  9 - 10

Case 1

Trouble 
position/
Cause

Defective installation of 
the harness to the CIS 
unit

Remedy

Check the harness 
connected to the CIS unit.

Note 

Case 2

Trouble 
position/
Cause

CIS unit abnormality

Remedy

CIS unit check

Note 

Case 3

Trouble 
position/
Cause

Scanner PWB 
abnormality

Remedy

Scanner PWB check

Note 

Main 
code

Sub 

code

Title

Phenomenon

Display

Lamp

Message

Details

While reading/writing the 
HDD system area data, 
the HDD returns an error 
response or no response 
at all for longer than 30 
seconds.

Section

Controller

Operation 
mode

Note 

Case 1

Trouble 
position/
Cause

No HDD is installed on 
the MFP control PWB.

Remedy

Check installation status 
of the HDD on the MFP 
control PWB.

Note 

Case 2

Trouble 
position/
Cause

HDD does not properly 
function.

Remedy

• CHECK connection 

between the HDD and 
MFP control.

• Perform an HDD read/

write test using SIM 62-
2/3.

• Replace HDD.

Note 

Case 3

Trouble 
position/
Cause

MFP control PWB 
abnormality

Remedy

Replace the MFP control 
PWB.

Note 

Main 
code

Sub 

code

Title

Main 
code

Sub 

code

Title

Phenomenon

Display

Lamp
Message

Details

Laser trouble
The BD signal from the 
LSU is kept OFF or ON.
When the polygon motor 
rotation is started and 
three successive BDT 
signals of I/O ASIC are 
detected after forced 
lighting of laser.

Section

Engine

Operation 
mode
Note 

Case 1

Trouble 
position/
Cause

The connector to the LSU 
or the harness in the LSU 
is disconnected or 
broken.

Remedy

Check for disconnection 
of the connector to the 
LSU.

Note 

Case 2

Trouble 
position/
Cause

The polygon motor does 
not rotate properly.

Remedy

Check that the polygon 
motor rotated properly or 
not.

Note 

Case 3

Trouble 
position/
Cause

The position of the laser 
home position sensor in 
the LSU is shifted.

Remedy

Use SIM 61-1 to check 
the LSU operation.

Note 

Case 4

Trouble 
position/
Cause

A proper voltage is not 
supplied to the power line 
of the laser.

Remedy

Replace the LSU unit.

Note 

Case 5

Trouble 
position/
Cause

Defective lighting of the 
laser emitting diode

Remedy

Check lighting of the laser 
emitting diode.

Note 

Case 6

Trouble 
position/
Cause

PCU PWB abnormality

Remedy

Replace the PCU PWB.

Note 

Case 7

Trouble 
position/
Cause

MFP control ASIC PWB 
abnormality

Remedy

Replace the MFP control 
PWB.

Note