What this means on these models
The door lock has to confirm, the programme has to be selected and started, and on many cycles a delay or a child lock can hold everything without any fault at all.
What owners of these models report
- It starts only after being switched off and on — A control that needs a power cycle to accept a start is a real fault, but an intermittent one rather than a dead machine.
- The drum hums but does not turn — Power is reaching the motor and something is stopping the drum, so this is a jam or a motor fault rather than a no-start.
- A delay-start time is counting down — The machine is doing exactly what it was asked. It is worth checking before anything is opened.
- No lights, no display, nothing at all — That is supply: socket, plug, fuse or breaker, and it is the shortest branch of this diagnosis.
- The display lights but the cycle never begins — The machine has power and is waiting for a condition - a lock, a selection, or a gate it cannot pass.
Causes, most likely first on this family
- Control board failure — A board swap on a guess is the most expensive way to be wrong here.
- Door not latched or the lock not confirming — The lock is the gate before every other step, and a door that looks closed but is not latched is the classic version.
- No supply at the socket — Free to test: a tripped breaker, a failed socket or a plug that has worked loose behind the machine.
- Child lock or delay start engaged — It produces an apparently dead machine with nothing wrong.
Working the fault in order
- Check both taps are open before concluding nothing is happening — A machine waiting for water looks idle from across a room, and this check costs a moment.
- Check the breaker and any fused spur behind the machine — It is the finding that explains a dead machine with a live-looking kitchen.
- Listen for the lock click with the door held closed — A lock that never clicks with a properly closed door has earned suspicion; one that clicks moves the diagnosis downstream.
- Press the door firmly until it latches and listen for the lock — The lock is the first gate the machine checks.
Before you open anything
Safety
Unplug the washer or switch off its breaker before removing any panel. A capacitor can hold a charge after the power is off, and on a drum machine the motor control board is the last thing to let go of it.
Models in the WAW family
Reference| Model number | Family key |
|---|---|
| WAW28420AU | bosch:washer:waw |
| WAW28440AU | bosch:washer:waw |
| WAW285H1UC | bosch:washer:waw |
| WAW285H2UC | bosch:washer:waw |
| WAW28620AU | bosch:washer:waw |
| WAW28640AU | bosch:washer:waw |
| WAW28790AU | bosch:washer:waw |
When to call a technician
A technician is the right answer as soon as the suspect is the bearing or the spider. Both are drum-out repairs, both are priced close to the value of an older machine, and both deserve a firm diagnosis before any money is spent.
