Error 3 when making scans in duplex mode it is showing E 3 . as per manuals it problem with front optical unit. is there any solution to set/repair optical unit?

Hi Adil, 

This E3 error message means ADF backside scanning optical alarm (upper optical unit ADF) which indicates ADF (back) lamp intensity check. Please follow the steps provided below:

1. Is the lower glass (white sheet guide)of the reading section dirty?

Open the ADF, and clean the sheet guide (white part) and the glass.

# When operating the scanner, the ADF’s inside glass becomes very hot. Take serious caution as the heat can cause burns. Before you clean the inside of the scanner, turn off its power and unplug the AC adapter from the outlet and wait (at least three minutes) until it gets cold.Be careful not to pinch your fingers when the ADF cover is being closed.
Note: Cleaning should be done approximately every 10,000 sheets scanned, though it may vary depending on types of
documents scanned. More frequent cleaning is necessary when the following types of documents are scanned:
- Smooth surface document such as coated paper
- Documents printed on almost entire surface
- Documents processed with chemical materials such as carbonless paper
- Paper with a high calcium content
- Pages with pencil lead
- Document where toner is not fused sufficiently.

If the above does not help, then the issue is caused by any of the followings for which you may have to contact the Fujitsu Expert/Engineer.

1. Upper Optical unit ADF may be dirty. (Remove any dirt inside of the mirrors and lens of the Optical unit ADF with blow brush. Do not use air sprays which may build up condensation on the mirrors.)
2. Upper lamp may not be functioning properly.
3. The connecting cables might be damaged.
4. The connectors are not connected properly.

Hope the above information is helpful.Please revert you have any doubt.

Regards,

TechSatya