Dryer Bosch MAXX7 sensitive does not turn-on

overview_dryer

Bosch MAXX7 Sensitive
E-number: WTE843A2

Description of failure

The dryer does not turn-on at all or turns-off automatically during usage.

Failure investigation

The internal power supply, a flyback topology, has died. There is no stable output voltage of the flyback converter. Measuring the internal body-diode of the integrated switch shows a short. Things to replace:

Flyback controller: TNY 266PN
2x Output capacitors 22 µF, 105 °C After replacing the broken components, the dryer works totally fine.

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