The car is 4 years old. The air bag deployed because of the 'clock spring' wiring shorted. The clock spring is located behind the steering wheel, behind the steering column. It contains the wiring for the horn, airbag, radio controls, etc. Suspect nothing wrong with airbag but main due to wiring.
Proton gave the standard answer 'Car out of warranty period'. So went to Proton parts center in Shah Alam and bought the horn cover (with horn) and clock spring (no more air bag for me). The air bag module cost Rm998.
The clock spring module is also known as mosquito coil (mun heong) by mechs. Cannot open because it's spring loaded, so I don't know how Proton can check if there is going to be a problem even if it's checked every day.
This can happen to ANYONE with air bag installed in your best car in the world.....
Just be careful.
First sign is your radio and electrical system go cuckoo.... within a short period of time, before you figure what happened the air bag will deploy prematurely........... imagine you are driving 110 km/h on highway.... dangerous le.....