MX-1800N (serv.man16). Section 8 - Self Diagnostics Trouble Codes - Sharp Copying Equipment Service Manual (repair manual). Page 10

MX-1800N  SELF DIAG AND TROUBLE CODE  8 – 10

 

* When the following combination (E7-09) where operation is not

performed properly is used. Local memory (slot 3, slot 4) combi-
nation

 

 

 

 

 

 

Trouble content

Local memory slot combination error

Section

MFP

Case 1

Cause

DIMM of other than 256MB is installed to the 
default slot.

Check and 
remedy

Check the combination of installed DIMM.

Case 2

Cause

DIMM of other than 256MB is installed to the 
expansion slot.

Check and 
remedy

Check the combination of installed DIMM.

1

–

–

E7-09

2

256MB

–

{

{

Normal operation

3

512MB

–

{

E7-09

4

256MB

256MB

{

E7-09

5

512MB

256MB

{

E7-09

6

256MB

512MB

{

{

Normal operation

7

512MB

512MB

{

E7-09

8

–

256MB

E7-09

9

–

512MB

E7-09

Trouble content

CCD black scan level abnormality when the copy 
lamp is turned off.

Section

Scanner

Case 1

Cause

Installation error of the CCD unit flat cable

Check and 
remedy

Check the installing state of the flat cable to the 
CCD unit.

Case 2

Cause

CCD unit abnormality

Check and 
remedy

Check the CCD unit.

Case 3

Cause

SCU PWB abnormality

Check and 
remedy

Check the SCU PWB.

Trouble content

CCD white scan level abnormality when the copy 
lamp is on.

Section

Scanner

Case 1

Cause

Installation error of the CCD unit flat cable

Check and 
remedy

Check the installing state of the flat cable to the 
CCD unit.

Case 2

Cause

Dirt on the mirror, the lens, or the reference white 
plate.

Check and 
remedy

Clean the mirror, the lens, or the reference white 
plate.

Case 3

Cause

Copy lamp  lighting trouble

Check and 
remedy

Check the installing state of the flat cable to the 
copy lamp unit.

Case 4

Cause

CCD unit abnormality

Check and 
remedy

Check the CCD unit.

Case 5

Cause

SCU PWB abnormality

Check and 
remedy

Check the SCU PWB.

Trouble content

Written register value cannot be read correctly

Section

Scanner

Case 1

Cause

SCU PWB abnormality

Check and 
remedy

Check the SCU PWB.

Trouble content

LSU BD signal is not detected.

Section

PCU

Case 1

Cause

Disconnection or improper connection of harness 
and connector between LD/BD PWB and LSUcnt 
PWB

Check and 
remedy

Check connection of the harness of each PWB 
inside the LSU.

Case 2

Cause

1)

Optical axis shift

2)

BK laser deterioration, power reduction

3)

BD PWB trouble

Check and 
remedy

1)

Use SIM61-1 to check the LSU operation.

2)

Replace the LSUcnt/BD PWB.

3)

If the trouble cannot be removed by the 
above 1) to 2), replace the LSU.

Trouble content

The color laser does not light up normally.

Section

PCU

Case 1

Cause

Disconnection or improper connection of harness 
and connector between LD PWB and LSUcnt PWB

Check and 
remedy

Check connection of the harness of each PWB 
inside the LSU.

Case 2

Cause

Y/M/C laser deterioration

Check and 
remedy

1)

Use SIM61-1 to check the LSU operation. 

2)

Replace the LSUcnt PWB.

3)

If the trouble cannot be removed by the 
above 1) to 2), replace the LSU.

Trouble content

Access error between the CPU of the PCU PWB 
and the LSU control ASIC

Section

PCU

Case 1

Cause

<When this trouble occurs in the initial process on 
turn on the power>
Communication connector trouble between the 
PCU PWB and the LSUcnt PWB (interface PWB). 
Harness trouble.

Check and 
remedy

Check the connector connection between the PCU 
PWB and the LSUcnt PWB (interface PWB).
Check the harness. If the trouble cannot be 
removed, replace the LSUcnt PWB or the PCU 
PWB.

Case 2

Cause

<When this trouble occurs on starting printing/
during printing, and SIM61-1 is used to check the 
LSU unit operation for each of B/W and COLOR 
and the judgment is NG.>
Connected the connector between the PCU PWB 
and the LSUcnt PWB (interface PWB) / Harness 
trouble

Check and 
remedy

Check the harness between the PCU PWB and the 
LSUcnt PWB (interface PWB). If the trouble cannot 
be removed, replace the LSUcnt PWB or the PCU 
PWB.

Case 3

Cause

PCU PWB or LSUcnt PWB (interface PWB) 
trouble

Check and 
remedy

Replace the PCU PWB or the LSUcnt PWB 
(interface PWB).