Electrolux W4105N, Service Manual

Page: 34 / 122

34
Troubleshooting
Fault code 32, MOTOR TOO HOT
This fault code is generated by the motor control. Each time the motor is
started from stationary, the motor control will first measure the resistance
between two phases in the motor. The motor control processor governs
the output transistors so that a determined DC current flows between two
phases in the motor winding. The actuation of the transistors is a measure
of the voltage applied to the winding and the resistance can be calcula-
ted using the current and voltage values. The resistance can then be
converted to a temperature since the winding resistance at 20°C and the
temperature coefficient are known. If the average value of the four latest
temperature readings is higher than the maximum motor temperature (e.g.
130°C), the ”Motor too hot” fault code will be activated.
The cause of high motor temperature can be a stiff drum, possibly in com-
bination with intensive use and high ambient temperature. There may also
be a fault in the motor (sticking bearings or short circuit in windings, which
impairs the efficiency of the motor). There could also be a contact fault in
the connectors between the motor control and the motor or a fault in the
motor cable. A fault in motor control temperature measurement circuits
can also occur.
Actions:
• Make sure the drum turns easily.
• Check the value on the fault code counter for fault code 32.
• Check the last 8 motor control fault codes.
• Measure the three phases to the phase resistors on the motor control
motor connector (disconnect motor control and take the reading in the
cable connector) to make sure they are the same.
• Start a 90°C normal program with load on continuous operation and
measure the temperature of the motor and motor control.
• Replace the defective part.