Door Lock Assembly - Midea CD400 Service Manual

VII. Check Internal Connecting Wire
The internal connecting wire connects the timer (60), the power switch (61), the inlet valve (95), the heating
elements (45) and other electric elements together. The wires shall be kept intact. Any damage to the wire
may cause overheat and result in broken wire. Common troubles to the internal connecting wire are broken
wire, bad connection terminal contact, and connection terminal insulation layer damages.
To repair the dishwasher, the ground shall be connected. When an electric component is replaced, check
whether the ground is connected again. This is a crucial step to avoid electric shock and short circuit.
Attention: to replace electric cord, use the cord of the same temperature resistance and specifications. The
specifications and temperature rise are marked on the cord.
Steps for the check:
Turn all the control knobs to OFF and pull out the power cord plug.
Open the outer casing, and, if necessary, remove the bottom pan.
Check the wires and connectors and replace the damaged ones.
VIII. Door Lock Assembly
micro switch
Slider
IX. Timer
The timer of the dishwasher consists of a synchronous motor and various switches, and controls the
various operations of the dishwasher automatically. The step motor, like a clock, runs at constant speed.
When it passes through the selected procedure, the internal switches will open or close at a precise
sequence, realizing the control of the circuit over the internal components.
The output cords of the timer are in different colors. With a copy of the circuit diagram in hand, you can
track the circuit from the timer to any element.
The timer is a very reliable unit. In case of dishwasher troubles, check other causes first before focusing
on and replacing the timer.
Steps for the check:
Turn all the switches to OFF and pull out the power cord plug.
An ohmmeter and the ability to read circuit diagrams are needed in this step.
Remove the outer casing.
Pull out the two input terminals of the timer motor and measure them with an ohmmeter (use the
range of R 100). If the pointer does not sweep partly across the line, replace the timer.
Refer to the circuit diagram to check the connection of the timer terminal to the elements.
The working mechanism of the door lock is that the linkage (8)
bolts up the door hook, which, in its turn, presses the micro switch
spring in the lock assembly to form a closed circuit. The lock
Micro switch spring
mechanism consists of the door lock holder (11), the slider (10)
and the micro switch (3). When the door is opened, the door hook
is withdrawn to release the micro switch, cutting the power supply
Linkage
for open door protection.
In case of worn out slider, micro switch failure or deformed micro
switch spring, troubles may occur and the dishwasher will stop to
work as usual.
Steps for the check:
a. Pull out the power cord plug prior to servicing the door lock
mechanism.
b. Remove the outer casing.
c. If micro switch failure is the case, disconnect the micro switch,
remove the two screws and replace a new micro switch.
d. In case of deformed micro switch spring, adjust the spring
with nipper pliers so that the micro switch returns to its
original position when the slider is released and the micro
switch closes when the slider is pressed tight.
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