Brother HL-3450CN Series, Руководство по обслуживанию

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HL-3450CN SERVICE MANUAL
5-9
2.3 DRAM Test Mode
This mode tests DIMMs installed on the main (video controller) PCB.
<Procedure>
1) To start the test program:
While holding down the Go button and + button, turn on the power. “DRAM CHECK
START” will be displayed. Press the Job Cancel button to start the DRAM check.
2) The LCD will display “START DRAM TEST”, and the Data LED blinks.
3) On satisfactory completion of all the RAM tests, the LCD will display: “DRAM OK!!”,
and the Alarm LED is on.
4) If any DRAM error has occurred, the LCD will display a fail message as follows;
5) Enter the hidden menu mode as follows to confirm the current memory map;
i) Press the -, + and Set buttons in this order while holding down the Go button.
ii) The LCD will display “HIDDEN PANEL”
iii) Select the “DRAM ADDRESS” menu using the scroll buttons.
iv) Whenever the Set button is pressed, the LCD will display the DRAM error address
on Slot 1, Slot 2, and Slot 3 in turn.
6) If a DIMM DRAM has an error, replace the DIMM corresponding to the above memory
map information.
Note:
x
There may be a case where the above sequence does not work correctly due to complete
RAM failure, or in faulty assembly such as a solder bridge or ineffective soldering etc.
x
“PRINT CHECK” may be displayed when exiting from the Test mode. It will disappear in
20 or 30 seconds, displaying “READY” on the LCD. It is not a fault.
RAM Address
WRITE data
READ data