D1coach

Took my car to dealer with what I thought was an alternator problem. The battery would run down and go dead even though it is only six months old. The problem turned out to be the alternator/starter/battery wiring harness, which I understand is a common problem on 05’s. The replacement harness is supposed to be heavier and not so susceptible to failure from heat as the original. The bill is close to $1500, luckily I have the aftermarket warranty. Mileage is 45,000.

From Suncoast website:

Updated Battery / Starter / Alternator Harness
Per Porsche's technical bulletin.

Issue: Battery discharged and/or will not charge properly. Voltage drop due to alternator-starter-battery harness damage at starter terminal. This issue is often mis-diagnosed as a bad battery, bad alternator, or bad starter, and these parts are often replaced in multiple repair attempts before the harness is determined to be the cause of the issue.

Fits all Carrera & Carrera S models, 2005-08.

fskof

Yes this is a common problem on the early 997s. There is a DIY posted on how to replace the alt-starter-battery harness.
When you get your car back you will be amazed on how quickly your starter will turn.

Sexonwheels

i did mine myself, cable was 132.00 took me five hours in my garage on couple of jack-stand. I am a licensed mechanic by trade but haven't worked as one in over 10 years, its really not that hard of a job. 1500.00 is outrageous to change that cable!!!!

D1coach

I misunderstood the SA over the phone, the bill turned out to be $860 total, not $1500.

sullivas

Can I get a copy of that bullitin from Suncoast website?

mgordon18

When the cable is the issue, is your battery actually dead? Or is the car just not starting due to the bad cable? In other words, will you need a new battery either way?

I think I had this problem a few months ago, but did not have this info at the time. My battery was only a year old. I ended up buying a new battery and it fixed the issue... for now.

USMC_DS1

It should be on Renntech.org... FWIW, they only allow you to view it and you cannot print it out. Wonder if it's something to do with legal liabilities.

sullivas

USMC-
I looked on Renntech.org but couldn't find it. I wonder if it came out in a later year. Do you know the number of the bulletin?
Thanks

D1coach

Sam - Here is a link to the page I quoted if that helps
http://www.suncoastparts.com/product...newproductpage

USMC_DS1

Hmmm... I can't find that one either but here are the R&R instructions if you need them. Before you start down this path... double check to ensure that the negative terminal ground strap is torqued down enough (11 ft-lb) on either end from the car battery to chassis. A loose connection at either point is known to cause issues as well. http://www.alldatadiy.com/alldatadiy...1149/132635514

FiatCoupe

My 2007 car was slow to turn over when hot but would start on the button when cold. I thought this was weird/annoying but normal. Eventually realized it wasn't normal and got the harness changed under CPO warranty.

You shouldn't need a new battery. Once the new cable is fitted more voltage from the battery will get to the starter.

John

sullivas

Thanks all

Banilej0

I've been wondering if this affected 07+ since most of the threads I've seen are for "early" cars like 05/06. I think my car cranks a bit slow but it always fires and doesn't seem to change between cold and hot starts. Will need to pay more attention from now on see if this could be an issue.

Is there a way to check if I have the updated cable?

jellonailer

I have this exact same problem on '07 997S

USMC_DS1

I used to think this was a potential issue with 07's and earlier cars but it seems that my car my be affected as well. I've kept my car on a trickle charger everyday and the Walmart battery is only 2.5 yrs old but lately it's taking longer to crank over. My SA noticed it this week and asked if they had switched over my battery wiring harness yet... I'll be making an appointment with my p-dealer shortly for my '08 C2S to have it checked out. Of course, it may just be the Texas heat sapping the battery.