Sony WM-EX674 Circuit Board

The Sony WM-EX674 printed circuit board (PCB) was an extremely successful design, which the WM-EX670, WM-EX672, WM-EX678, and WM-EX600 models also used. This circuit board, whilst complicated for most people to repair, is simple if you had the service manual, as it shows you all the test points where one may check for signals. However, due to the extremely small surface-mount device (SMD) components, repair requires great skill and experience.

Ribbon Cable

The ribbon cable shown in the photograph connects the audio head terminals to the PCB.

SMD Switch

These switches are very delicate and operate with light fingers. If they remain pressed in, then they are extremely difficult to replace due to their size.

Battery Contacts

These battery contacts are for the rechargeable battery. If there is any oxidation, then be sure to clean them and apply some electrical contact cleaner.

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