Driver side tail light on 2005 suburu outback does not work at times

10 yrs or 105K miles. Change the idlers, tensioner and water pump at the same time. Also change the thermostat and radiator cap (using subaru oem parts). Most aftermarket thermostats are junk.

It should be in the left front door.

Electrical issue or mechanical binding or breakage .

To open the bonnet, look for the lever inside the car. it will normally be located on the side of ether the drivers or passengers side footwells. simply pull the lever and bonnet should pop open.

You never replace any part, without a knowledge of what it is,how it works and how to test it.
So get access to the switch first,test,then move on to the motor.
I would get a wiring diagram, and start at the beginning of the circuit, and continue testing,as I went thru it.

Look in the owners manual it will tell you what fuses are what, if not you have to test each fuse with a test light

do you have a trailer hitch? if yes disconnect convertor box the light behind the dash should not be related bulb just out, also make sure bulbs you've changed are correct

The switches in Subarus are made by Nissan believe it or not. They are not interchangeable. Anyway, I suspect you have a bad window switch. You can pickup the whole bank of swiches or replace just the one. Do a search on ebay for your part.
Has this car had body damage on the driver's door? You could have a cut wire inside the door.

HI there! There is a switch on top of the steering column, make sure it is off. This happens all the time,they get bumped on and you don't realize it. Hope this helps! Thanks

On my 2004 Impreza ther is a switch on top of steering column that turns those lights on all the time. Look for that switch.