http://www.retrevo.com/support/Ariston-AWD-120-Washers-manual/id/866dj996/t/2/
To even contemplate trying to repair something like this you must have the service manual or service sheet, often inside the machine, under the inspection panel, when removed will reveal a troubleshooting manual.
https://secured.whirlpool.com/Service/SrvTechAdm.nsf/2cd44500d572193285256a45004fd9d6/f16b0618a09b52f6852574a5004b31c1?OpenDocument
Above is a generic service manual, if there is no sheet in the unit, this will help somewhat.
Now below is a dedicated self help washer repair troubleshooting site, all free, now between this website and
http://www.washerhelp.co.uk/diy-repair-help.html
You simply are going to have to troubleshoot to isolate and fix your problem,as may symptoms, look the same , yet have very differing Causes. It also would be good if you have a Multimeter, too. But as said it is all in the manuals and troubleshooting sites to know exactly what to do, step by step.
"Is it an overload switch that needs resetting? " (sic) No I do NOT think so.
"part of the electronics that may have failed ?" (sic) Yes i DO think you have had some sort of electronic, electrical, sensor failure.
"could it be the motor? " (sic) usually these stand up well, you can usually tell by the smell that a burnt out motor gives off, it is very distinctive. So NO I do NOT think the motor is bad. It is most likely OK. But never to be ruled out, until tested.
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