bambar

Recently bought a 2004 Cayenne Turbo, and noticed that some of the fuses in the right side (passenger area) are higher than the required value.

Does this affect operation in any way?
I know that a fuse is mean to protect the circuit to a component, and if it is higher than required then it may allow a higher amperage through which could burn the component.

Reason I checked my fuses was because my right low beam was not working, and I noticed the fuse for my right low beam has an amper value (30A) higher than what is required (15A).
I highly doubt it, but can this be the issue stopping the fuse from working?

Any help is appreciated!

deilenberger

The fuses are sized to (1) allow the needed current to flow to the device connected (2) protect the wiring in case of excessive current draw (short circuit, etc.)

#2 is the more important one. If the fuse is oversized and a short or partial short occurs - the wiring can overheat, causing at best some damage to the wiring harness, and at worse - death when it happens with the car in your garage under the house when it catches fire in the middle of the night.

I'd suggest installing the correct size fuses. If any keep blowing - do not increase the value - find out what is drawing too much current and correct that.

deilenberger

Oh - the reason your light isn't working might be as simple as the bulb, or if it's an HID light bulb or ballast. Or it can be the wiring going to the headlight has burned up from the heat. Rather common on a 955. You can replace the short section of harness that burns up. It's found behind the headlight, which is actually quite easy to remove. Consult your owners manual on headlight removal.

RT930turbo

Just being a smart azz, but in all seriousness I would replace them with the correct fuses to avoid melted wiring or fire if something were to short or go bad.

bambar

Thanks deilenberger.
Well, I did check before making this post and the wiring harness was in fact very damaged, so I ordered a new one which should arrive this week. But my gut feeling tells me its the ballast. Because all of the lights on the right side work except the low beam - so this makes me doubt its the harness.. but time will tell.
I was just wondering if the fuse could have been the cause.

bambar

Thanks for the visualization! I guess I'm going to have to replace them with the correct fuses... Just makes me wonder why the previous owner had them arranged like that.

nodoors

Good call on getting it right. Thermal runaway in wires is a real thing.

With regards to wrong fuses - 99 out of 100 times it is just laziness or incompetence of the previous owner.

19psi

I'd have to look at my '04 owner's manual again to refresh my memory, but there is a misprint in it that had me thinking the previous owner installed a bunch of wrong fuse values.
I want to say the manual referred to the right side as the left side.

Just went out and looked at my manual...

Page 289 at the top:
Fuse assignment - fuse box in left side of dashboard

Page 292 at the top:
Fuse assignment - fuse box in left side of dashboard

If you happen to flip through to page 292, those are actually all the assignments and values for the RIGHT side.

bambar

I have to say, the fuse topic on the 2004 Cayenne Turbo is quite frustrating. I started out by looking at the user manual but then gave up, as a lot of the assignments did not make sense. I then managed to look around and find someone who put up the fuse assignments on an image, and it was completely different.

Very very frustrated with this, and to be honest, not sure which fuse diagram to trust.
On the owners manual here: http://www.porsche.com/all/media/pdf...yenne_pcna.pdf
the fuses can be found starting on page 315. Not sure if this is what you meant.

19psi

That's a different manual than the one included with my '04.
Everything is correct in my manual except they needed to say RIGHT side of dashboard on page 292.

Just a simple but very confusing misprint which could cause disastrous results.

For me, I was adding a bluetooth setup to my stereo system and wanted to pull the radio fuse.
I opened up the manual and looked for RADIO in the chart, found the fuse number and above the chart it states fuse box in left side of dashboard. I notice the fuse isn't even close to being the proper rating and pulling it didn't kill the radio.
I flipped back a few pages and see another chart (also for the left side) and it was all the correct circuits and ratings. I remembered seeing a door on the passenger side and sure enough, that was the one I needed to be in.
Blamed myself until I went back and looked at the manual.