Sharp SF-2220 Service Manual page 138

[10] SERVICING AT MEMORY TROUBLE AND MAIN CONTROL PWB RE-
PLACEMENT
1. General
The EEPROM in the control PWB and the EEPROM are storing
various set values, adjustment values, and counter values.
These data are very important and used for operating the machine
properly and for service control.
In the following cases, therefore, various set values, adjustment val-
ues and counter values must be set again.
* When memory trouble (U2) occurs.
* When the EEPROM in the main control PWB is replaced.
* When the main control PWB is replaced.
When "U2" trouble occurs, the data cannot be relied upon, and they
must be set properly.
2. Purpose
The purpose is to reset the memory data to operate the machine
properly.
Use the attached service memory data recording sheet to memorize
the newest data when servicing in order to cope with the above
situations. This improves efficiency in servicing and realizes quick
recovery.
3. Remedies
Perform the procedures according to the following flowcharts.
"Sim" in the flowchart means "Simulation."
Memory trouble
Procedures for memory trouble, main control PWB replacement,
and main control PWB EEPROM replacement
10 – 1
MC-Service
NO
Repair the
defective section
Replace the main
control PWB
Is the
NO
Mount the EEPROM of
EEPROM in
the old main control to
the main control
the new main control
PWB defective?
YES
Replace the main
control PWB
1
"U2" trouble
occurs
Do you replace
the main control
PWB?
YES
Replace the main
control PWB
Cancel "U2" trouble
with simulation 16
1
Replace the
EEPROM in the
main control PWB
Replace the EEPROM
End