Just a note to say thanks for all the folks on this thread 18-year-old machine working fine. PCB repaired no flashing light! To stop the jumping with a heavy load that caused the problem in the first place (blown PCB fuse, 2-way relay burnt out - £5 spares from RS components) unit is back in...
It might be a relay on the control board that has fused itself in the ON position
There are photos here of the problem related to failure due to bad shocks. This blows the rotate / reverse relay and a fuse.
If you check the diagrram in the thread you can see what relay you need for the heater...
Check the brushes on the motor a new set is around £6 on ebay
If the motor is ok it is the controller (new relay and fuse) £8 or £24 for a board repair by post
Replace the shocks This is why the fuse and relay blew £30 ebay
Details pics and info here...
In in the same boat W842 16 years old, heavy load and the rinse light flashes.
Removed the motor brush are fine. Resistance across PINs 3 and 4 is between 3 and 4 ohms
Cleaned up the motor reffited same problem. Pump spinning, filters all clean. Drain hoses removed and clean. Felt the pipe...