Fuse Substitution Question

orph · 10-10-2002, 02:16 PM

Fuse for the right turn signal is blown ( 911 Turbo ). Electrical diagrams as well as the old fuse both would indicate a 5 amp replacement fuse is what is required. However , no one locally nor does Pelican offer a 5 amp fuse, the 8 amps being the only thing apparently readily available.

Would replacing with an 8 amp be an "ok" fix, or too big ?

Jim Sims · 10-10-2002, 02:24 PM

Don't do it! 911 wiring is marginal and if a short is causing the 5 amp fuse to blow an 8 amp fuse will allow more than twice the power or heat to flow or be deposited (heat or power goes as the current squared). This could melt the shorted circuit's wires, which could then melt the adjacent wires in the wiring harness. Then you'll be facing a big, expensive mess. Find the short and fix it and then install the proper fuse. 5 amp fuses are available; I got a package a few months ago via an aftermarket source. Jim

Mike Feinstein · Mike Feinstein's Garage

I have the exact same issue. I fixed a short and replaced the blown 5 amp fuse with an 8 amp fuse. I've gone to four autoparts stores and called two suppliers (including our host) and came up empty on the 5's. Interestingly, there is another 5 amp fuse for the right side running lights that was apparently replaced with an 8 also. Seems the PO had the same issue at some point.

If you find a source for 5 amp fuses, please let me know!

Thanks,

pwd72s · 10-10-2002, 04:05 PM

Mike, did you check a NAPA store? Buss fuses makes replacements for VW fuses. They are glass tube style, but the ends are pointed to clip into the fuse holders of the german cars designed for the ceramic fuses. My (rapidly) fading memory thinks there was a 5 amp offered in this style. But if you're really into originality, this wouldn't do...

Mike Feinstein · Mike Feinstein's Garage

pwd,

No...but I will stop by a Napa store tomorrow and see what they have. I'd prefer the ceramic type fuses but I believe the integrity of my wiring is more important than originality. Thanks for the tip.

autobonrun · autobonrun's Garage

Quote:

Originally posted by pwd72s
Mike, did you check a NAPA store? Buss fuses makes replacements for VW fuses. They are glass tube style, but the ends are pointed to clip into the fuse holders of the german cars designed for the ceramic fuses. My (rapidly) fading memory thinks there was a 5 amp offered in this style. But if you're really into originality, this wouldn't do...

Agree, I picked up some 5a and 25a glass tube fuses at our local Napa when no one else had the 5a.

Ove · 01:56 AM

Hi, guys,

If you cannot find the fuses locally I could buy them here and send them to you. You have checked at Pelican?

They are plastic and come in 5A, 8A, 16A or 25A

10 fuses are around $2

Ove · 10-15-2002, 01:57 AM

Here's a pic.

reed930 · 10-15-2002, 02:52 AM

Orph,

I too had a hard time locating the 5 amp fuses. The Porsche dealership did not have the 5 amp fuse in stock when I needed one, and the service technician said they use the 8 amp fuse in place of the 5 amp all the time. In the end, the dealership special ordered a few for me. They were a bit more expensive than at an auto parts store, but how often do you need to replace a fuse?

The Porsche part number for the 5 amp fuse is 900 173 006 90. I think the dealer charged me $.70 each for them. I don't know how much cheaper you can get them from NAPA, but sometimes it is just easier to order parts through the dealer. I am sure the later type fuse will work, but I liked the color coded fuses, and even though it's a small thing, for an extra $.25 I feel better keeping things original.

Hope this helps.

Wil Ferch · 10-15-2002, 05:26 AM

Guys:
I may have said it before...but if Porsche designed the electrical system for 5A ( and others at 8A, 16A, etc)...then it is insane for anyone..let alone a *dealer* ...to substitute 8A for 5A. May even open up legal actions. 8A is 60% stouter ( ! ) than 5A.....don't think of it as only a 3A change !!!.

---Wil Ferch

makaio · 10-15-2002, 05:56 AM

Listen to Will on this.

Seven-Seven · Seven-Seven's Garage

Not sure if this is the size (length) you're lookin' for, but here's what NAPA is offering online in the way of GBC ceramic 5-amp fuses:

http://www.napaonline.com/cgi-bin/ncommerce3/ExecMacro/NAPAonline/search_results_product_detail.d2w/report?prrfnbr=15625429&prmenbr=5806&usrcommgrpid=

tmctguer · tmctguer's Garage

thanks so much for the online store tip. i've struggled to find the 5 amp fuses, too.

i was going to order 10 from the online store, then got to the checkout phase and saw $4.90 for parts and $5.00 for shipping. time to print out the page with the part number and swing by NAPA in person !!

Seven-Seven · Seven-Seven's Garage

I had a similar online buying/shipping experience two days ago. I was at checkerauto.com's webpage hoping to purchase the Dorman switch referenced in this thread: Factory looking switch for OIL cooler fan.

The part is only $2.99, but the shipping is a whopping $14.00! You would think that they would offer an alternative shipping method when sending small items that weigh a few ounces! Needless to say I cancelled the online transaction and plan to visit the store later this week.