Hotpoint SDL510 flashing lights

Whatever cycle I try on my Hotpoint SDL510, after 5 or 10 minutes the Washing and End (3 hours and 9 hours) lights start flashing and the machine drains. The door to the tab compartment does not open during the cycle, and the Salt light is permanently lit (though this may be coincidence). I’ve checked the filters and they seem to be clean. Any ideas? The manual doesn’t offer any clues.