LOCKED MOTOR ERROR
Cause
Wash pump motor error code
Solution
Check motor windings resistance value and check for proper voltage to the wash pump motor.
Wash Pump Variable AC Voltage 3 wires = 24 ohms & voltage is variable AC 50~170Vac.
Also check for possible obstruction or debris in the pump stopping the impeller from turning.
Older model dishwashers (typically 2016 and older) may have a hall sensor. If working on a model that shows a hall sensor on the wiring diagram click here to jump to that information:
DETAILS BELOW:
Check the connectors for proper connection. The new style dishwashers with the variable AC voltage use a 3 pin RED connector on the main board with wire colors BLUE, SKYBLUE & WHITE. See the picture below.
Check the pump impeller for foreign item or stuck. If the impeller is damaged or stuck then replace the Wash Pump assembly.
Check the resistance of the Wash Pump motor windings for 24 ohms ± 10% between any two of the motor wires, white to blue, white to sky-blue, blue to sky-blue. If resistance is out of range or any windings read open then replace the Wash Pump assembly. See the example below from the newer style dishwashers. (For the older style dishwashers that have a Hall Sensor see after this illustration).
The Wash Pump motor is a 24Vdc Brushless Motor using pulse width modulation dc voltage but can not be measured using a multi-meter set to DC voltage. You will have to use a multi-meter set to AC voltage. The multi-meter needs to be a higher quality meter capable to read high frequency inverter pulses to get any meaningful voltage readings.
Check the Wash Pump motor voltage for 50~170 Vac when running. You may choose to enter the test mode and activate the Wash Motor to test this voltage. The lowest speed in test mode is 150 RPM and the Main board should be putting out around 50Vac. The highest speed in test mode is 500 RPM and the Main board should be putting out around 170Vac.
If the Main board does not produce any voltage for the Wash Motor then replace the Main board.
If your wiring diagram shows a hall sensor as shown below then use the information below to test the Hall Sensor and Wash Motor…
5 Responses
RNN231214004707
RNN240119065056
RNN240128002936
We should add LE code info on older LG dishwashers. The ones with the hall sensor built in. Like the LDF7774*
Done.