Elliotw44

I am comparing two different wiring harness part numbers. Both part numbers description in PET is similar. any suggestions or tips for figuring out differences?

Part number: 997-612-521-29 Description: Wire set 1 FRONT luggage compartment F >> A9-AS783 448 D - MJ 2010>>
Part number: 997-612-521-30 Description: Wire set 1 FRONT luggage compartment F A9-AS783 448 >> D - MJ 2010>>

The differences have been bold in the description. Maybe its making mention to cars before and after certain VINs?

Petza914

The last 2 digits are the version number of the part that's determined by the first 9 digits. When that part was first made it ended in 00,then it was revised and became 01, etc so it has gone through 30 revisions with superceded part #s since first released, but I can't tell you what was changed from one to the next.

Bruce In Philly

2009 C2S 193K miles

Is your car a 2010? MJ 2010 is German for Model Year 2010.

As Pete noted those last digits are some sort of revision number and we assume there was an improvement to the part but we really don't know. Maybe the increment is the result of a difference in supplier... we just don't know. I always seek the most recent part, the highest number, but regardless, any part with any sequence number will fit and work. I have seen that sources such as eBay may have an older number. Usually if you buy from a dealer such as Suncoast, you get the latest number as long as their old stock was exhausted. I have sent emails to Suncoast asking what sequence number they would ship and they have been great telling me what they have on stock... also if you give them your VIN, they will ensure you get the correct part for your car.

It helps you download the latest catalog from the Porsche website as they do update it occasionally.

Peace
Bruce in Philly (now Atlanta)

Elliotw44

Is it always superceded? or can be it be different version of a similar part number. In this case depending on the options a given car has the front wiring harness is different. So they have similar part numbers but different final two digits.

Current Theory:
If we look at MJ2010>> that means model year 2010 and forward.
Now I apply the same logic used in the >> to the F section of the description
>> A9-AS783 448 cars with a VIN prior to 448?
A9-AS783 448 >>cars with a VIN 448 and after?

Petza914

The coils revision and the starter and alternator harness are good examples. The updated coils have the same 9 digit part number and a different last 2 digits - that change meant a thicker insulator was used so the coils would last longer before the insulators cracked due to heat and exposure. Either coil will work on the car but the later one lasts longer.

On the starter / alternator harness, the way the crimp connection at the starter with the pigtail that then goes to the alternator is a different, larger, and more robust metal piece. That was done to prevent the voltage drop that caused the slow start situation when the car was warm. In my case, because my engine bay is jammed with a supercharger, the newer, larger crimp connector on the new cable actually touches my supercharger hardware and created a major short, so that upgraded, superceded part number causes a disaster in my car - obviously, Porsche can't account for the aftermarket and what may have been done in their car, but sometimes a superceded part number is an improvement in an all original car, but doesn't work at all in a modified car, so just going with the latest iteration is not always the answer. I actually tried to fine a new version of the old cable with the old part number, but couldn't. Mine was still in good shape, so I modified my cable and my car has never started better.

Elliotw44

After a Conversation with 9XX I have confirmed this theory and the F section of the description is denoting before/after certain car VINs.