Miele g660 gets stuck on main wash & final rinse?

The programme gets stuck just after the soap dispenser opens. If I move the rotary control on a couple of clicks it proceeds OK until the end of the final rinse when it gets stuck again. A couple of clicks on and it finishes fine.
Miele suggested a fault with the thermostat which is not indicating when the washer is up to temperature or with the element, which means it actually isn't getting up to temperature.
It gets pretty hot, so I think the thermostat is working.
I've found what I think is the thermostat, but it could be the safety cut-out? ELTH 262 3439781 T130. Can't find one online. How do I check if this is broken? It has continuity at room temperature? Serial number 20/45207932.