SHARP FO-375
Service Manual

UX-41DE FO-375DE

3. Diagnostic items description 3. 1. Soft switch mode
Used to change the soft switch settings. The soft switch which is stored internally is set by using the keys. The available soft switches are SW-A1 to SW-L2. The content of soft switches is shown in page 2-5 to 2-15. The contents are set to factory default settings.

3. 6. Signal send mode
The mode is used to send various signals to the circuit during FAX communication. Every push of START key sends a signal in the following sequence. Moreover, the signal sound is also output to the speaker when the line monitor of the soft switch is on. [1] No signal (CML signal turned on) [2] 9600bps [3] 7200bps [4] 4800bps [5] 2400bps [6] 300bps (FLAG) [7] 2100Hz (CED) [8] 1100Hz (CNG) [9] END

3. 2. ROM & RAM check
ROM executes the sum check, and RAM executes the matching test. The result will be notified with the number of short sounds of the buzzer as well as by printing the ROM & RAM check list. Number of short sounds of buzzer 0 � No error 1 � ROM error 2 � RAM error (32Kbyte)

3. 3. Aging mode
If any document is first present, copying will be executed sheet by sheet. If no document is present, the check pattern will be printed sheet by sheet. This operation will be executed at a rate of one sheet per 5minutes, and will be ended at a total of 10 sheets.

3. 7. Memory clear mode
This mode is used to clear the backup memory and reset to the default settings.

3. 8. Shading mode
The mode is used for the shooting compensation. For reading, set up the special original paper. The shooting compensation memorizes the reference data of white and black for reading. Moreover, the memorized data is not erased even if memory clear mode is executed.

3. 4. Panel check mode
The mode is used to check whether each key operates properly or not. Press the key on the operation panel, and the key will be displayed on the display. Therefore, press all keys. At this time, finally press the STOP key. When the STOP key is pressed, the keys which are not judged as "pressed" will be printed on the result list. � LED port of the contact image sensor (CIS) is kept on during the term from when start of the panel test mode to end with the STOP key.

3. 9. All black mode
The mode is used to check the state of the printing head and intentionally overheat it. Whole dots are printed over the interval of 2 m. If it is overheated or the printing sheet is jammed, press STOP key for the end.

3. 5. Check pattern mode
This mode is used to check the status of print head. Two sheets of check pattern are printed. The following information of check pattern is printed.

3. 10. Auto feeder mode
Approx. 35 mm In this mode, a document is inserted and discharged to check the auto feed function. After this mode is started, set a document, and the document feed will be automatically tested.

1 Vertical stripes (alternate white and black lines) 2 Full black 3 Full white

Approx. 70 mm Approx. 35 mm

3. 11. Message print mode
Used to print the displayed message of communication for translate each language.

1
3. 12. Ring & Dial free mode
Used to reject dial tone check while autodialing is carried out. And used to change the bottom Ring frequency of auto-receiving to 13Hz.

2

3. 13. Cutter aging (Cutter model only)
The mode is used to continuously cut the recording paper to approx. 10 mm and display the number of cutting times.

3
RANK 0 or 1

(Unless the memory clear is executed, the number of cutting times is integrated.) In the following cases, the operation is stopped. 1. The stop key is continuously pressed. 2. There is no recording paper. 3. The recording paper is jammed.

Note: There is a selection RANK 0 or 1 depending on resistance value of the thermal head. RANK 0 or RANK 1 is printed at the tail of check pattern to identify.

2�3