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Franc Zabkar Franc Zabkar is offline
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Default Bosch washing machine burned out capacitor and transformer...

On Mon, 10 Nov 2008 11:42:35 -0800 (PST), put finger to
keyboard and composed:

My Bosch Washing machine isn’t working very well – it won’t move to
the rinse part of any program.


Are there any visual indications that suggest that the CPU *thinks*
that the washing machine is in its rinse cycle?

Taking it apart, it looks like it has burned out a 470uF Capacitor
(400v) and maybe a small transformer (Marked “KA 19/04” and 063.783 )

The capacitor seems to have stained the circuit board and the
transformer seems to be covered in soot

Which would explain the burning smell :-)

Now, I think this transformer is the low powered supply to power the
brain (and the LCD) which is still working (!!)


Am I right about what this transformer is doing?
Does it sound like it needs replacing?
If I replaced it, might it fix the problem?
Might I just need to change the capacitor?


The 400V capacitor is probably the bulk capacitor which filters the
output of the mains bridge rectifier. If the power supply to the CPU
is working, then this cap is probably still functional, although if it
is visibly leaking or swelling, it should be replaced.

If I need to replace the transformer, can someone help me identify a
replacement as google seems to struggle with it.

Its about 15mm by 10mm and stands about 12mm off the board.
It seems to have 2 contacts on one side and a center tap on the other
– though this is not actually connected to anything.

Thanks


Hmm, so it's not a transformer, but a coil, or choke. What does it
connect to?

BTW, uploading a photo to your web space might help.

- Franc Zabkar
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