Hotpoint WT741 1400 spin timer erratic

hello all.

im steve new to the forum today,and am a fully qualified electronics

engineer,with a background in digital and analog,have repaired/restored

rebuilt vintage music amplificatrion for many years,also spent time in the

world of digital electronics,military,and commercial,that out of the way,here

is my problem,hotpoint WT741 1400 spin washing machine,has an erratic

timer,sometimes goes above the display time,may be on say 45 then goes

direct to over 50,then starts dropping again,then will do same again,and

at times go back to start,it is not a control module fault,or edge connector

issue,the module was sent away to specialist,tested no fault found,also an

alternate controller was tried,same result,i was told by he who tested the

above,heater may be breaking down and suffering earth leakage,my next

step is to disconnect that,and run the machine through cycle,and see what

then happens,is it possible the display front board could be a suspect,there

is not much else in here,maybe the actual drum motor,but that seems fine

anyone out there know exactly what this is,i'm sure there is,many thanks

folks.steve