Rigth side marker fuse
 

I noticed that my right side tail light was out. I tested the light bulb by switching it from side to side and the bulb turned out to be ok.

I finally tracked it down to the right side marker fuse (I think position A3). Trouble is, every time I replace it, immediately blows immediately.

I am not a sparkie by any stretch of the imagination. Where (and how) do I start looking?

You, or someone, will have to start tracing wiring until you find the short.

I realize this sounds very stupid, but how do I do that?

That's not stupid. I wouldn't know where to start on a vehicle like a Boxster. If I was to try, I guess I would start from the effected turn signal and work forward from there. Otherwise I would drop it and the keys off at my dealership and let them figure it out.

Look for water or corrosion in the light socket first , then check any wiring
connection points on that circuit.

Good luck,
Nick

I think this is a bit better at explaining it than I might be. I wouldn't recommend following the directions to the letter, especially if you're not confident in your skills in dealing with electrical wire maintenance, but also because this is very general and you shouldn't go chopping up your car's wires. You can at least strat tracing before you drop the car off to a specialist, possibly isolate the general area of the short, and understand what you're actually looking for.

How to Find Electrical Shorts | eHow.com

EDIT: One thing I can definitely say that's mentioned in there is don't go hunting with the battery still connected. You'll fry your meter. And you don't need just an ohm-meter, just go get a multi-meter if you don't already have one, and ensure that it can read resistance in ohms, and you're good.

I removed the side marker and the tail light circuit board tonight and put in a fresh fuse in.

When I switched the light switch on and POP.

%%$&* !!!!!!!

So, I am assuming that the short is somewhere in the wiring harness.

You really need a wiring diagram to help you map out what to do.

Basically you will find out what is in that circuit, unplug and check those connections, follow the affected wires until you find your short.

try using the parking light for side of road (European set up for narrow streets) and see if fuse blows. If it doesn't, wiring is probably good and headlight switch is likely bad (very possible as they are known to crap out).

Good luck and see owners manual if you don't know what I'm referring to.

:)

Thanks guys,

I downloaded the wiring diagram. It shows only the side marker (right side and right rear) on circuit breaker A3.

With all components removed from that circuit, it still craps out on me.

Will the light switch only affect the right side circuit?

Did you try the parking light check like Burg suggested?

Ok, I just went after a fresh batch of fuses and popped one in. When I turned the light switch to Park, the right side marker fuse (A3) popped again.

I still had the side marker and the tail light circuit off.

Does this mean that the switch is suspect? Or could it still be somewhere in the harness?

Is headlights pod still in place? Why not pull it out and try again...

Did you turn it to the parking lights (one click clockwise) or to park setting counterclockwise?

I dont understand. Headlight pod? You mean I should remove the headlight? I can certainly do that, however I was focusing on the items on the A3 circuit.

I turned the light switch two notches counter-clockwise to the park setting.

Two notches CCW is the parking lights for the left. One would be for the right, based on the arrows on either side of the "P" symbol. The switch lights the side marker and taillight of the respective side you set the switch to. Also, these only function when the car is not running.

And I believe he was indeed referring to you pulling out the headlight when trying. Remember, you're trying to isolate the source of your short.

Even more curious that it would blow the right side circuit. Unless it blew as I moved it past the first notch.

I will remove the headlight and keep looking

Ok, I found the problem. After A LOT of troubleshooting, I found that the front park light bulb had burnt out and fused against the socket. That caused the short.

The bulb that I pulled out of there looks strange though. I have not seen it before. Looks like the following:
http://ep.yimg.com/ca/I/yhst-3182566..._2185_27428520

I see that they are available on ebay, but cannot seem to find anything else about them. Anybody know?

Thus my suggestion to remove headlight pod...glad you found source. Those are crap aftermarket LED bulbs. Without a proper resistor and heat sink, they were bound to overheating and cause a problem one way or anothet. Find correct replacement bulb using either guide in any parts store or by going to:

OSRAM SYLVANIA - SYLVANIA Home

Select consumer products, auto lighting, replacement guide and then select your car from the drop down menus.

Good luck :)

PS- it goes w/o saying...pull the one in the drivers side too before it causes damage...

+1, good to see that you found your problem without having to send it off to a dealer or mechanic...and before you ate any more fuses. :p

Some day, someone will make an affordable LED lighting setup that is truly plug-and-play, but until then, people get what they pay for, and whoever dropped those in there before you took the super cheap way out.

Hey, there's another DIY for you, crumbum, go get yourself a soldering iron and make your own LED driving lights. ;)