Trouble code f11 or fdl for whirlpool duet front load wash machine.

Hi.

FDL is door lock. This is the first part to be tested, since it can be symptom of a wiring problem.

The door lock is tested by reading impedance on the door latch contacts.
If the door lock is OK, do the following troubleshooting for F11. The problem is usually CCU.

F11 is communication error between CCU (main control unit) and MCU (motor control unit - additional control module connected to motor and to CCU, located in a sealed box inside the washer).

This usually means that either CCU or MCU is defective. In some case the connectors or the wiring harness connecting the two modules is the problem.

The tech sheet says:

F11:Serial Communication Error
Communication between the Central Control Unit (CCU) and the Motor Control Unit (MCU) cannot be sent correctly.
Solution:
* Check Wire Harness connectors to the MCU, the motor, and Central Control Unit (CCU)
* Check the Drive system for any worn or failed components
* Check MCU
* Check CCU
* Check Motor
* Check Wire Harness

The wiring harness is tested using a multimeter to ensure that there is continuity between the MCU and CCU connectors. If a single wire is good it will read zero Ohms (closed) from contact to contact.
Motor is tested reading Ohms, it must be read about 6 Ohms on three different pairs of contacts.
Drive system in motor is checked observing if any of the parts are broken.
MCU and CCU are tested reading volts during operation and testing at component level. The testing must be done by a tech. Check CCU to see if there is any sign of failure (eg burnt spots).

Most of the time the problem is CCU. Trick to repair it include testing and eventually reheating the solder joint of the two on-board relays, cleaning connector contacts with circuit cleaner solution. This in case that the problem is CCU.

Disconnect the unit from power for five minutes as first test. This will reset CCU.