Determining Which Electronic Requires Replacement (Electronic Test Procedure) - Miele W1903 User Manual

W1900 Series Clothes Washers
5.13 Determining Which Electronic Requires Replacement
(Electronic Test Procedure)
Correct zero crossover point (NND) recognition is required by the
microprocessor to provide a reference point for activating relays and
thyristors. The zero crossover point of the sine wave is the basis for the
time measurement of the microprocessor.
If the Electronic Unit fails to detect the zero crossover of 3 half waves of
the AC power sine wave, a fault is registered and the microprocessor
resets. The current program is cancelled and the LED's switch off. The
appliance can only be restarted after switching it off and then back on;
and selecting a program.
Because the possibility exists that either Electronic could present the
same type of fault condition; the following procedure ensures the correct
component is diagnosed / replaced.
Service Tip:
In the event the Control Electronic Unit or the Power Electronic Unit
is suspected to be faulty, this procedure must be performed.
Figure 5-10: Ribbon Cable with Pin 1 Position Noted
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Technical Information