I have a 2002 subaru Impreza with the power light flashing and transmission acting frantically which affects the steering of the car,stop switch off and start back and it fine until it does it again.

yeah, it's the brake light switch (just above brake pedal)

Yes, the lights of the Subaru Impreza 2002 light on when you pull up on the brake pedal

Try the park lamp switch on top of the steering column

there ie a switch for parking lights on top of steering column ..i bump it all the time!

so flipping the indicator switch doesn't affect the signals lights? It sounds like the electronic flasher module has gone bad. This will be located under the dash near the steering column (don't know exact location as it varies on car). The unit will be labeled

replace the transmission speed sensor.

DIPSTICK IS HIDING UNDER A POWER STEERING HOSE ON THE DRIVERS' SIDE, NEAR THE BACK OF THE MOTOR. HE WILL NEED A LONG FUNNEL TO PUT TRANSMISSION FLUID IN THE DIPSTICK TUBE. IF IT SAYS ADD, THEN ADD A PINT OF FLUID. HOPE THIS HELPS. THANKS IN ADVANCE FOR AN HONEST RATING. BEST OF LUCK. THANKS FOR USING FIX-YA

if by a/t you mean automatic transmission try a power purge transmission service it may have a filter sensor that is telling you to service soon

There is a switch on top of the steering column that switches the parking light facility on and off. Check that this switch is not in the on position . If it is on then your side lights will stay on even if you turn the lights off.

I had the same problem--turned out there's a switch on the steering column behind the steering wheel. You've probably found it by now, but wanted to share :)