Bosch Classix 6 F21 fault code (brushes replaced) but still does not operate (relay clicking periodically)

Hi all,

I've had this machine for some time, maybe 10 years or so.

I replaced the brushes some time ago as they were worn out and the machine stopped working the other day "after making a noise when spinning." It may have also tripped the house RCD.

When I got to it, there was an F21 error on it, which I believe means the motor is not operational (won't spin or maybe no current?)

I've replaced the brushes and spun the motor by hand; the brushes were in contact with the commutator OK.

Reset the F21 and put the machine onto spin.

The machine drains but then a relay clicks about every 30s for about 1-2s, which I imagine is it attempting to start the motor spinning but it does not turn.

If I leave the machine for 5 mins or so, it'll continually do this clicking. If I try on a freshen up, the machine fills but the clicking occurs with no drum movement. The motor and drum are free to turn.

I've had a meter on the exposed brush connections and there is no 240V when the relay is operating or not.

I suspect that something upstream is faulty - maybe the control board (dry joint or track blown off), relay contact etc.

What I don't understand is why there is no F21 fault code again if turning the motor on results in 0 speed.

Any ideas on what to do next?

I'm already thinking of replacing the machine given that it's old - don't really want to be spending 90 quid on a control board etc if it may not fix the problem.

Thanks in advance for any help.