Haha.. RF engineer 1, Porsche dealer 0

[skip_168]

I love being an engineer.. check this out:

I have a 2000 boxster, and of course the remotes quit working...

So, I bring the keys into the Lab where I work, mostly RF(radio frequency) stuff, and check them out...

I used a Rhode & Scwartz Real Time Spectrum Analyzer,($175,000 piece of test equipment), and characterize the transmitter in the key. The keys transmit a digital code on an individual carrier frequency.. pretty weak though, I got almost 40 db above the noise floor 1 foot away, and 15-20 db three feet away.. basically what this means is that our remotes' range SUCKS! pretty week for a transmitter.. ya gotta be almost to the vehicle before the signal will get through doors, glass, seats, bla bla bla... But basically, my keys work fine.

So I call the dealer and it goes like this:

Porsche dealer: service, can I help you?

Skip: Yeah, I have a 2000 boxster and my remotes don't open the doors any more..

Porsche: does the red light in the key work?

skip: yep, and they have new batteries...

Porsche: well, you need new keys, and reprograming, Parts & labor for 2 keys and programming, $450

Skip: Are you sure? what if the keys work fine?

Porsche: no, the keys don't work, they stop transmitting... its always the keys..

skip (in my best engineering voice):
well, I'm a RF engineer and I used a Rhode & Scwartz Real Time Spectrum Analyzer and characterize the transmitter in the key. The keys transmit a digital code, which I demodulated and have written down, on an individual carrier frequency. I got almost 40 db above the noise floor 1 foot away, and 15-20 db three feet away,so my keys are transmitting....

Porsche dealer: uh... oh..... mmmm.. ok, well then your car needs to be reprogramed for the keys...

skip: how much is that?

Porsche: 60 bux...

skip: Ok, I'll bring the car down friday & we can try that... thanx...

Porsche: uh... ok...(click)



Now as fun as this was, I might need new keys, but I need to do more research, on the forum...

They did say I needed a bar code for the keys, but all that has is the code the keys transmit, which I have.. I can tell you one thing, I wont spend $187ea. for keys..

so I'm off! as any engineer, I love a challenge!

[BoxsterLewis]

I just had this done and it was 300 for the Head part and not the key, my light blinked and everything also. Im a systems engineer so i had no clue about that lol.

Here is what I would recommend. Will the Rhode & Scwartz Real Time Spectrum Analyzer fit in the Boxster? If so, bring it home, and sell it on eBay. Then buy a brand new Boxster! This will be a lot cheaper.

[skip_168]

Originally Posted by bmussatti

Here is what I would recommend. Will the Rhode & Scwartz Real Time Spectrum Analyzer fit in the Boxster? If so, bring it home, and sell it on eBay. Then buy a brand new Boxster! This will be a lot cheaper.

Yes it will fit, but we keep track of that stuff pretty well, I'm sure they would wonder where it went.. most of they time we use it to demodulate our local radio station.. a $175,000 radio.. that sounds like crap!

[skip_168]

Originally Posted by BoxsterLewis

I just had this done and it was 300 for the Head part and not the key, my light blinked and everything also. Im a systems engineer so i had no clue about that lol.

did they give you a card with a bar code on it for each key? If so, that is the code the keys transmit.. so if you dont have the cards, you have no choice but to buy new keys.. unless of course, you have a sectrum analyzer with demod capabilites layin around..

[silver arrow]

Originally Posted by skip_168

did they give you a card with a bar code on it for each key? If so, that is the code the keys transmit.. so if you dont have the cards, you have no choice but to buy new keys.. unless of course, you have a sectrum analyzer with demod capabilites layin around..

Now where did I put mine? I keep misplacing mine. Sounds like a good little side business you could start up. De-code keys. I'll be your first customer. :dance:

[Burg Boxster]

Unfortunately, they probably need the barcode itself so they can feed it into the computer. Then using a database, get the freq values/codes (which yes you have) into their software for programing the car. It's much like a UPC barcode in stores. The clerk probably doesn't know and could care less what price is printed on a sticker or sign, it's all about what's in the database and they don't know that until they scan the barcode.

That being said, all you need to do is find out is the barcode format they use and convert your values into it a barcode. Basically the barcode "idiot proofs" the process for a technician who [most likely] has very limited RF experience. Their process is probably not a two way system which could easily be subject to technician error (or worse - exploitation). That'd be my guess at least.

Anyhow, if someone has a picture of their barcode tag from a new key, please post it. I can try to scan and decode. If the freq values are in the code itself (we'll compare to the info you have), we might be able to make a corresponding barcode for you.

Good luck!

[kyle986driver]

Originally Posted by skip_168

.. basically what this means is that our remotes' range SUCKS! pretty week for a transmitter.. ya gotta be almost to the vehicle before the signal will get through doors, glass, seats, bla bla bla... But basically, my keys work fine.

My keys only work from about 3 feet away too. I believe i heard somewhere that Porsche designs this low range in for security purpose. Whether thats true or not, its a pain.

Good luck with it!

[Burg Boxster]

Kyle-

Yours might not be the same issue. If it truly is just a lack of distance from vehicle there is a TSB. In a nutshell, it has to do w/ the length of the wire from the remote antenna in the driver's side A-pillar. You can easily do a modified TSB yourself by exposing and the length of wire needed from the harness insulator (see solution below). That should work - it does on most 986s. If need be, you can do the full TSB (again DIY) by trimming up the antenna wire to the required length (from the black sheilded portion) and again exposing outside the harness insulator.

Here a link to when it was discussed before - solution link is in my post (#2)

Remote Extender Hack

[LoveBunny]

I have no clue what half of this stuff means, but if I ever have a problem with my key I know who to ask for help!

When I got my car my dad asked me how many keys I had. I told him two. He goes, "Don't lose those. They are expensive to replace." Huh? Like I was planning to just lose my key for the heck of it?

[kyle986driver]

Originally Posted by Burg Boxster

Kyle-

Yours might not be the same issue. If it truly is just a lack of distance from vehicle there is a TSB. In a nutshell, it has to do w/ the length of the wire from the remote antenna in the driver's side A-pillar. You can easily do a modified TSB yourself by exposing and the length of wire needed from the harness insulator (see solution below). That should work - it does on most 986s. If need be, you can do the full TSB (again DIY) by trimming up the antenna wire to the required length (from the black sheilded portion) and again exposing outside the harness insulator.

Here a link to when it was discussed before - solution link is in my post (#2)

Remote Extender Hack

Thanks, that looks like it will fix my problem. I will be doing this this weekend!

[skip_168]

Originally Posted by Burg Boxster

Unfortunately, they probably need the barcode itself so they can feed it into the computer. Then using a database, get the freq values/codes (which yes you have) into their software for programing the car. It's much like a UPC barcode in stores. The clerk probably doesn't know and could care less what price is printed on a sticker or sign, it's all about what's in the database and they don't know that until they scan the barcode.

That being said, all you need to do is find out is the barcode format they use and convert your values into it a barcode. Basically the barcode "idiot proofs" the process for a technician who [most likely] has very limited RF experience. Their process is probably not a two way system which could easily be subject to technician error (or worse - exploitation). That'd be my guess at least.

Anyhow, if someone has a picture of their barcode tag from a new key, please post it. I can try to scan and decode. If the freq values are in the code itself (we'll compare to the info you have), we might be able to make a corresponding barcode for you.

Good luck!

This is all true... these guys at the dealer just scan & press the "yes" button.. now I did have a bit of luck.. I found a paper tag with a barcode, part number and other letters on it.. I bought my car used, so I don't know if it is for the key.. here is the bad news.. I only found 1. there should be one for each key.. its a valuable clue though..

anyhow, I'll post up a pic asap..

[skip_168]

Originally Posted by Burg Boxster

Kyle-

Yours might not be the same issue. If it truly is just a lack of distance from vehicle there is a TSB. In a nutshell, it has to do w/ the length of the wire from the remote antenna in the driver's side A-pillar. You can easily do a modified TSB yourself by exposing and the length of wire needed from the harness insulator (see solution below). That should work - it does on most 986s. If need be, you can do the full TSB (again DIY) by trimming up the antenna wire to the required length (from the black sheilded portion) and again exposing outside the harness insulator.

Here a link to when it was discussed before - solution link is in my post (#2)

Remote Extender Hack

yeah that will work, but DO NOT TRIM THE WIRE! unless you are absoulutly sure that it will not touch any metal.. this will gnd the Antenna and you will get nothing.. the insulation really doesn't matter much... just get the antenna out of the wire harness & out side the metal A pillar...

oh, replace your batteries too...

you can check your batteries, which have a DIRECT impact on range, this way:

THe key draws about 10mA when transmitting...

a new battery will have a voltage drop of about .2 volts(from 3.2V static to 3.0 when you press a remote button), and this puts out the max power of the transmitter...(about 40 db above the noise floor)

my old battery dropped to about 2.4V.. and droped the output power of the transmitter by 60%!

so, replace your batteries, & do the TSB mod, and thats the best it will ever be...