So I was getting tired of hearing the VW beetle-like "bip bip" of the 997 alarm horn on door unlock, but I like having it as a audible confirmation.
The Cayenne, Audi cars and BMW's have a nicer euro-sounding electronic chime. I picked up a Cayenne alarm horn from Sunset Porsche for $70 and will wire it in next week.

If anyone else is interested in DIY I'll post how it went and some sound / vid clips.
Looks to be pretty straight forward, the 997 alarm horn is 2 wires (+12v pulse / -ground), and the Cayenne electronic horn is 3 wires:
Pin1- Lin-Bus pulse signal
Pin2- -ground
Pin3- +12v battery

So we can see right off the bat that the Pin1 Lin-Bus is not going to be compatible. Need to convert this to standard 2-pin +12v pulse and -ground like the OEM mechanical horn.

UPDATE 01/16/2009:
What I am using:
1J0 951 605 A - MY05+ Cayenne / Audi / VW electronic siren + battery backup - $70 from Sunset Porsche in Oregon
3D0 973 703 - plug connector for siren - $8 from Sunset Porsche
000 979 131 - wires for connector - You need three of these for the connector, $4 each from Sunset Porsche
* You can order these parts from any VW / Audi / Porsche dealer, I recommend www.sunsetporsche.com for theri outstanding service and low prices.
The connector and wires are actually Audi part numbers, and the electronic horn is the same for late model VW / Audi / Porsche

This is what the alarm siren and plug with assembled wires will look like:


But, I need to modify the internal wiring for standard 2-pin 12v operation. The Pin1 of this horn uses a CCM Lin Bus signal to turn the horn on / off. We need to use regular 12v.
Cutting the case open is very easy with a razor knife, just score around the outside edge seam until it comes apart. took me 10 minutes to pop it in half, and it is a clean cut / easy to reassemble with adhesive.

I will post pics and instruction after I have figured out modifications to the internal wiring- looks simple.

 

Whats the 'bat' connection for, then?

 

When I lock or un-lock my Carrera S there is no alarm horn or bip bip sound. Just the light flash. How are you getting a sound when lockin gand unlocking?

thanks!

 

Minok- I'm thinking the batt connection is for the internal electronics of the chime horn. The stock 997 horn is mechanical so only needs constant ground and a positive pulse.

mdrums- You might be able to turn on the audible lock / unlock confirmation in the OBD functions of your S (If you have sport chrono- I don't). If not then it's a quick trip to your dealer to have it enabled. Usually they will do it for free, some places will charge you $50. I also had my drive-off door lock function turned on, if going over 5mph the doors lock.

I installed the SmartTop from www.mods4cars.com which allows you to enable / disable the audible confirmation through it's settings.

 

RemoteKey or SmartTop for a cab!!!!
Sorry , I missed above post!!

 

If you have a 997 cab, RemoteTop and RemoteKey have been integrated into one product called SmartTop (about $500). Hands down the BEST #1 mod for any cab. period. I swear the car should have come from the factory like this, it even greatly improves how the window switches work.
If you have a coupe, I think you can just get RemoteKey. Still worth it for the window switch remapping and other added conveniences.

 

I'm still waiting for them to come out with a SmartTop for the Targa models to handle opening and closing the Targa roof with the windows. Eg, having the remote roll down both windows and open the top would be sweet (no more oven car by the time I get there).

Having it work the way the VW's do, where using the key in the door lock to lock the car (and hold the lock position ) to close all of the windows and Targa top would be welcomed as well.

 

I'm very interested in turning on my audible chime for lock/unlock. I have a Carrera S with Sports Chrono and, to my knowledge, I haven't been able to find anything that will turn this on/off.

For those who went to the dealer, is there a function I need to point them to?

Thanks in advance

 

Dealer should know exactly what to enable for audible confirmation- pretty straight forward. You might also want to have them turn on the drive-off door locking, convenient feature for safety.

 

Hey Kurt, where you been hiding? I'd like to figure out how to get the alarm to even sound (chirp) on opening and closing the doors. Any ideas?

 

LOL- Yeah.. I have been working way too much! Hope you had a good Holidays and New Year.

So are you talking about the audible confirmation on door lock / unlock? You'll either have to dealer-enable that feature or install the RemoteKey product.
https://www.wit-usa.com/sms/shop/ind...ew&idlistpos=1

I also had the dealer enable my daytime running lights and drive-off door locking.

 

The DRL and Drive-off-locking can be set with the computer config (if you have Sport Chrono, I think).. but I'm not sure about the audible confirmation on lock/unlock.

 

But, I need to modify the internal wiring for standard 2-pin 12v operation. The Pin1 of this horn uses a CCM Lin Bus signal to turn the horn on / off. We need to use regular 12v.
Cutting the case open is very easy with a razor knife, just score around the outside edge seam until it comes apart. took me 10 minutes to pop it in half, and it is a clean cut / easy to reassemble with adhesive.

I will post pics and instruction after I have figured out modifications to the internal wiring- looks simple.

Can you post your pictures, mine is a UK car and it already has this exact alarm fitted, I wanted to see the internals of the unit.

I think the battery in it is dead. The main car battery went flat and since i have had to disconnect this as it keeps bleeping and actually going off but quietly, no full volume, even when the car is running

 

I agree, the horn on the 997 is weak to say the least.