REMOVING THE TOP CASE
- Reverse the instrument and remove the three M3 pan head screws.
- Open the top casing in the direction of the arrow shown below.
- Release the lock of the film cable connector with the small flat blade driver and your finger as shown in the expanded illustration and remove the film cable.
REMOVING THE LCD ASS'Y
- Remove the top casing as described.
- Remove the four M3 pan head screws with spring washers which are marked with circles shown below.
- Disconnect the LCD ass’y cable from the ECG control board.
- Lift up the LCD assy so that the LCD assy flat cable is perpendicular to the ECG control board and pull out the LCD assy film cable from the connector on the ECG control board to remove it.
REMOVING THE THERMAL HEAD ASSEMBLY
Do not touch the surface of the thermal head with your bare hands. This can cause some dots of the thermal head to malfunction. If you touch the surface of the thermal head, clean it with the provided thermal head cleaner pen or cotton moistened with alcohol.
- Remove the top casing as described.
- Remove the LCD assy as described.
- Disconnect the thermal head assy connector from the thermal head assy.
- Push the thermal head bracket fixed rib in the direction of the arrow shown below and lift off the thermal head bracket from the thermal head bracket fixed rib. If the thermal head bracket is not removed completely, push the other side of the thermal head bracket fixed rib the same as above and completely lift off the thermal head bracket.
- Remove the thermal head springs from the thermal head spring hooks.
- Remove the three M3 pan head screws with spring washers.
- Remove the top casing as described.
- Remove the LCD assy as described.
- Remove the thermal head bracket as described.
- Remove the two M3 pan head screws holding the motor assy to the bottom casing.
- Disconnect the motor assy connector from the ECG control board.
- Remove the bundle of leads which connects the mark sensor board and ECG control board from the lead hook.
- Remove the M2 pan head screw with spring washer holding the mark sensor BD earth plate to the bottom casing. The motor assy does not contain the motor sensor BD earth plate.
- Lift off the motor sensor board with the motor sensor BD earth plate.
REMOVING THE SPEAKER ASSEMBLY
- Remove the top casing as described.
- Remove the LCD assy as described.
- Disconnect the speaker assy connector from the ECG control board.
REMOVING THE INVERTER BOARD
The inverter board has a high voltage circuit for the LCD backlight. This can cause shock up to 10 minutes after the power is turned off. After the power is turned off, wait 10 minutes before disassembling the instrument.
- Remove the top casing as described.
- Remove the LCD assy as described.
- Remove the M2 pan head screw holding the inverter board to the ECG control board.
- Remove the bundle of leads which connects the inverter board and ECG control board from the mini clamp on the power unit.
- Disconnect the inverter board connector from the ECG control board.
- Lift off the inverter board from the ECG control board.
REMOVING THE ECG CONTROL BOARD
Local language text is stored in the flash memory on the ECG control board. When the ECG control board is replaced, local language text is not available; only English text is available. To use the ECG with your own language after the ECG control board is replaced, you must reload the local language files to the ECG. Refer to the YZ-012H6 Translator Support Tool operator’s manual.
- Remove the top casing as described.
- Remove the LCD assy as described.
- Remove the inverter board as described.
- Remove the three M3 pan head screws with spring washers.
- Remove the two spacer bolts 1.
- Disconnect the thermal array assy connector from the ECG control board.
- Lift off the ECG control board from the power board. The CNJ035 connector on the ECG control board is directly connected to its socket on the power board.
REMOVING THE POWER UNIT
- Remove the top casing as described.
- Remove the LCD assy as described.
- Remove the inverter board as described.
- Remove the ECG control board as described.
- Remove the ground terminal assy.
- Remove the two M3 pan head screws with spring washers holding the power unit to the bottom casing. Be sure to use the correct length spacer bolt when replacing the power unit. The two types of spacer bolts which are used in the power unit are almost the same length.
- Remove the three spacer bolts holding the power unit to the bottom casing.
- Disconnect the battery terminal assy connector from the power unit.
- Remove the ferrite tape holding the thermistor wire to the battery compartment.
- Remove the battery cover plate. Do not completely lift off the power unit from the bottom casing before removing the thermistor. Otherwise, the thermistor wire will break.
- Slightly lift up the power unit and pull out the thermistor from under the rechargeable battery.
- After pulling out the thermistor, lift off the power unit from the bottom casing.
