Wow, what a piece of junk this thing is. Cheap and chincy, no wonder they have such a high failure rate. The wires are small and not very well connected for a device that must carry full motor current.
Here's a pic of one with my test cable for locking/unlocking the latch. I use a zip cord power cable with two 1/4" male non-fully insulated quick disconnect lugs that fit perfectly into the connector. You just very quickly plug/unplug the AC plug into a socket to switch the lock. The solenoid inside the assembly is only meant for a brief pulse of AC to make it operate. Do not leave it energized. The solenoid mechanism is bistable, once locked, it stays that way and once unlocked, it stays that way. If you come across a washer that will not unlock due to a control board problem, you can use this cable to unlock it assuming the latch is otherwise ok. You can check the solenoid winding by checking resistance across the white and yellow wires. Should be between 85-155 ohms. Once locked, you can also check continuity of the lock switch between white and red. You will need a magnet to activate the lid switch for testing it between white and blue.
As long as the solenoid coil is good, you can take this thing apart for repairs. You can clean the contacts of the switches if neccessary and if the wires aren't making good contact with the internal metal strips, you can just strip them and solder them to the strips.
In order to get it apart, you must use an exacto straight blade or similar to cut down the plastic protrusions that prevent the clips from opening fully as shown in these pictures.
Once open, this is what you see.
Here's a closeup with description of operation. The wire connections are ID (insulation displacement) and are fine for low power applications but not great for powering motors, in my professional opinion. They should have used the lock switch to activate a triac on the control board as is done for the hot (L1) side of the motor power feed. The neutral carries the same current as the hot side and shouldn't be run through this cheap switch. Just my professional opinion of course. I'm just a tech, not an engineer.
Here you see the blocking element protruding below the mechanism. It goes into the slot in the trap preventing it from moving back and keeps the lid strike in position. If you force it open, the breakaway section will break loose allowing the trap to move and releasing the lid strike. Once the breakaway piece is gone, the spring steel strip under it raises and will prevent the blocking element from lowering which prevents the lock switch from closing.
You can easily remove the lock switch spring contact to clean the contacts. In fact, you can easily completely disassemble the whole thing. The solenoid just lifts out but be careful you don't lose the spring on the solenoid plunger.
Here's a link to the patent for this device with detailed description of operation.
All images and text © 2013 Eric Fairbank