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trube78 · 06-06-2007, 08:44 PM

On the left hand side of the radio slot there is a medal tab than is normally not grounded to the radio (with the radio removed it sticks out a quarter/half inch or so.) If you look at your Porsche radio you will see a piece of plastic glued to the side than stops the ground. When you installed an aftermarket radio, there is no plastic piece so the radio is grounded on that side. This causes the horn to beep when the alarm is set. When you set the alarm, the alarm system arms and protects everything but your radio (same thing happens if you leave a trunk, door, center console or the top unlatched.) The single beep is to let you know the alarm is not fully set -- in your case the radio is not covered.

If you wish to stop the horn beep, you should remove the radio and put plastic or tape (duct tape works well) over the spot on the new radio in an analogous spot to your old Porsche Radio. Depending on your new radio this may or may not protect the radio. OEM radios have a circuit that ensures it is alarmed (as I recall a light blinks on the radio.) Some aftermarket radios have a similar alarm that if wired up correctly will set if the tab is not grounded (the plastic is in place.) Others do not.

So how are you not protected. If your top is up the only way to easily beat the alarm is with the keys. If the top were cut anyone entering the car would trip the alarm by setting the motion sensors off or opening a door. However, if the top is down (and you do not use a red clip) the motion sensors are off and someone could hop into the car (as long as they keep the door closed) without tripping the alarm and remove the radio. Realize that without the proper alarm circuit in the radio you may not be protected anyway.

The other disadvantage is that you will always get a beep. To some this is an advantage since it lets you know the alarm is set and the doors are locked without checking the lights flashing . However, if you leave a trunk ajar you will always get the beep so ... you would not know. When I installed a new radio in my 2002 I eventually removed the tape since I liked the beep. In my 2006, I wish I had a beep sometimes. Been thinking up a hack to install a beeper (not the horn) but the wiring diagrams for a 2006 are tough to find.

Hope this helps.
ATB,
Tom

06-06-2007, 08:44 PM	#7
trube78 Registered User Join Date: Jun 2005 Location: Blacksburg, VA Posts: 49	The radio alarm On the left hand side of the radio slot there is a medal tab than is normally not grounded to the radio (with the radio removed it sticks out a quarter/half inch or so.) If you look at your Porsche radio you will see a piece of plastic glued to the side than stops the ground. When you installed an aftermarket radio, there is no plastic piece so the radio is grounded on that side. This causes the horn to beep when the alarm is set. When you set the alarm, the alarm system arms and protects everything but your radio (same thing happens if you leave a trunk, door, center console or the top unlatched.) The single beep is to let you know the alarm is not fully set -- in your case the radio is not covered. If you wish to stop the horn beep, you should remove the radio and put plastic or tape (duct tape works well) over the spot on the new radio in an analogous spot to your old Porsche Radio. Depending on your new radio this may or may not protect the radio. OEM radios have a circuit that ensures it is alarmed (as I recall a light blinks on the radio.) Some aftermarket radios have a similar alarm that if wired up correctly will set if the tab is not grounded (the plastic is in place.) Others do not. So how are you not protected. If your top is up the only way to easily beat the alarm is with the keys. If the top were cut anyone entering the car would trip the alarm by setting the motion sensors off or opening a door. However, if the top is down (and you do not use a red clip) the motion sensors are off and someone could hop into the car (as long as they keep the door closed) without tripping the alarm and remove the radio. Realize that without the proper alarm circuit in the radio you may not be protected anyway. The other disadvantage is that you will always get a beep. To some this is an advantage since it lets you know the alarm is set and the doors are locked without checking the lights flashing . However, if you leave a trunk ajar you will always get the beep so ... you would not know. When I installed a new radio in my 2002 I eventually removed the tape since I liked the beep. In my 2006, I wish I had a beep sometimes. Been thinking up a hack to install a beeper (not the horn) but the wiring diagrams for a 2006 are tough to find. Hope this helps. ATB, Tom