Indesit WiDL126 won't move on from initial wash cycle?

On programs beginning with a wash cycle, the machine fills and appears to wash; green light 1 is on. But this continues indefinitely. Stopping the machine will allow me to run the rinse, spin and drain cycles.

Program 12 does its cold wash and refills for the wash cycle; then as above.

Program 1 appears to start the pre-wash, but the doorlock and three green lights horizontally to the left start to flash while the pre-wash continues.