1. Remove the battery pack, memory card and lower case.

2. Remove the AC/DC unit.

3. Remove the main chassis and motherboard.

4. Short-circuit the two terminals of the high-voltage capacitor with a short bar, which is connected to the ground terminal on the wall through a ground wire.

5. Remove the four M3 flat-head screws with spring washers that secure the high-voltage capacitor to the lower case, and then remove the two high-voltage capacitor retaining brackets.

6. Remove the caps from the CNP552 and CNP553 wires from the high voltage capacitor.

7. Remove the high voltage capacitor.

8. Remove the three wires (CNP555, CNP554 and CNP556 wires) from the high voltage inductor that connect the high voltage inductor to the relay unit.

9. Pull out the relay unit.

NOTE: High voltage capacitors can store lethal energy. Always discharge the capacitor before touching any high-voltage component of the instrument (high-voltage capacitor, high-voltage inductor, relay unit, paddle socket, or paddle).

During the use of Nihon Kohden Cardiolife TEC-7621C Defibrillator, if there is a problem with the Relay Unit HV-761V, an error code will be displayed. Next, take a look at what the different error codes mean:

1. A501: During standby mode, the HV capacitor has more than 1 J energy more than one continuous second

2. A512: When charging starts, the high-voltage capacitor energy does not reach 1J within 2 seconds.

3. A513: The energy did not reach the selected energy within the specified time.

4. A524: After charging, the capacitor energy drops to the specified value for each energy.

5. A527: After charging, the capacitor energy is approximately 15% higher than the selected energy.

6. A529: After charging, the actual charging capacity is different from the selected capacity.

7. A556: Internal discharge takes more than 20 seconds to complete.

8. A566: 20 seconds after adjusting the internal discharge, the voltage of the high-voltage capacitor did not reach the target value.

9. A585: The high voltage capacitor voltage exceeds the specified voltage.

10. A587: When using disposable pads, 12.5% or more of the charged energy remains in the high-voltage capacitor after 2 seconds of external discharge.