Can be one of a few things. I found wire that a wire to Thermistor had been chaffing on the pully belt and had worn through giving the same problem ERROR code 5.
I joined the wires together again and taped back out of the way and Hey Presto all fixed. This is the little thing with two wires on just above the heater element.
It could also be the Thermistor that is broken or more than likely the heater element.
Easy fix can all be done with the back off and the POWER OFF.
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