I unplugged it (from the electrical outlet) each time and it didn't help. Do you mean unplug the TMP47C222 chip from the socket? Thanks.

 

I unplugged it (from the electrical outlet) each time and it didn't help. Do you mean unplug the TMP47C222 chip from the socket? Thanks.

I think he meant unplug it from the outlet. That's what you did. So when you unplug it after the 3rd (good) cycle , you plug it in and it would continue with two bad cycles, right?

 

I would look at the solder on D6, R8 and S6 and clean off the flux. I would also focus on the stress points headers and other I/O terminals reflow these points. Perhaps there is a vibration issue. If you can access this with power on perhaps in can be reproduced with cold spray or by gently moving parts.

 

Looking at the picture I see 2 relays. My guess would be one for heating element and the other for turning motor. Since your problem is intermittent I would start looking for a sticky relay. Sounds like turning relay may stick once in a while messing up the cycles.
To verify this:
Method
1/ Attach a couple wires to the energizing coil and ground to monitor voltage while unit is going through a cycle and see if motor does not stop if the voltage has indeed dropped. (Voltage across D1)
2/ Externally energize relay with external power supply and see if contacts move both ways freely.
3/ The relay top can usually be removed and take a visual look at moving parts.
Hope this helps,

 

if i was you id remove the relays and test those contact wise,sometimes you may be able to open them up for contact cleaning if they arent the sealed type.also,topside of the board ,R8(150k resistor) looks like one end has been desoldered(looks like the topside earth connection,i take it this is a double sided pcb) the side nearest the large ic.
also a big problem with these boards is sometimes due to the plug/socket edge connectors-check soldering here and the crimped connectors themselves.