Yaris MMT Transmission

[Dupont]

Hello, I have a 2006 Yaris with MMT gearbox. It has 36,000 miles on it and runs really well and in excellent condition.

However, it has developed an annoying fault that occurs once in a while. I put car in neutral and start engine as normal then wait a second or two before putting it into E to move forward, but instead of that happening I hear a loud clang from engine/gearbox area and then the N starts flashing and I cannot select any gears. Also a red light is displayed on dash like a star shape.

If I do nothing and wait a few hours then the car starts fine and gears can be selected or if I disconnect battery and wait ten minutes before reconnecting it starts up fine. The red light has gone and gears are selected fine.

Any ideas as I am at a loss?

Thanks in advance.