Passenger headlamp lights and then goes out sometimes comes back on. . The driver's side headlamp did the same thing about a year ago and the mechanic replaced headlamp. . . Short or lamp?

The passenger side is grounding threw the drivers side. When you pull the drivers side light the other looses it ground. It is actually grounded threw the bulb. The reason it is dim. It could be the plug. Find the ground and run a new one to the bulb from the body.

Interesting question. Bulbs do burn out, but premature failure is often caused by overvoltage from the alternator. Have your dealer check the alternator for correct voltage AND waveforms. You can check it yourself with a multimeter. If the battery voltage is more than about 14.5Vdc, eg 15+, the alternator has to be replaced.

Does seem odd,never heard of Subaru having that odd habit.
I would have thought your dealer would have checked but if not have them or someone check the charging system output.

Generally, it is better to replace both at the same time, simply because the possibility of the other one following after. BUT $150.00? wow, that is not something that would void your warranty if you replace it yourself. The bulbs are as cheap as $7.00 at your local parts store. Save yourself $130.00 and replace them yourself. ^^ Good luck and hope this helps. P.S. If you are talking about the entire headlight assembly, then $150.00 is more than fare.

When HID headlamps start doing that, it is usually time to replace the HID unit on whichever side is messing up. I hope you have lots of money, because Cadillac is very proud of their headlamp units!

BMW and Mercedes had the same problem. They changed the type of grease used to assemble the door latch mechanism.

WD40 Squirted into the lock area often does the trick.

Roll down the window and aim nozzle/straw at interior latch mechanism.

Put WD40 straw into key hole and squirt .

Did you replace the DRL Relay in the fuse panel located on the drivers side dash? There is also one out in the fuse block under the hood.

This sounds like a loose connection/bad wire somewhere for the low beam lights. Can't really give you more information without seeing the vehicle, and wiring diagram for the circuit. Usually, things that go on and off when hitting bumps are connection/wiring problems. The fact that one of your low beam headlamps burnt supports this theory. Bad connections or wiring mean lower voltage, thus higher amperage at the bulb, motor or whatever it's running, which makes them burn a lot quicker.

These cars have a CAN system and almost anything from a sunroof control module to a door control module to a software update can cause ALL of these problems. Unfortunately 99's and 00's are the years that exibit these problems most often. There may even be a shorted wire under the driver's seat. Good luck and please find someone you trust as the explanation may seem like it does not make sense.

Check the fuse for the passenger side.It is under the hood. it may not be making good contact. wiggle it a little bit and see if it makes any difference. if not, check where the the ground wires are connected to the chasis. See if thats not the problem.