Need a bit more information - as there is not enough info here to help you.
What model and year of Toyota are you referring to?
What engine light are you referring to - the engine check light? Or the other dash lamps that come on when you first turn the key on?
What is exactly happening - is the engine not turning over, or cranking? Do you hear any clicking or ticking noise? Do any lights at all come on when you turn the key to the run position?
Did you check that the battery is working (lights work, dome lamp comes on)? Any indication that there might be some malfunction, other than the light does not come on (leaking, car hasnt run for some time, car has all fluids, car has been tuned up)?
Any events taht could have caused this to happen (car was recently worked on, radio or other electronics replaced, car been in an accident)?