Alarm Lock, internal resistance values
 

According to the diagram in the Bentley manual, the alarm lock has 2 different internal resistance values (one for 'off', one for 'on'). Since I didn't get the key from the PO, and Porsche no longer seems to make the lock and key, and you apparently can't get the lock re-keyed, I thought I'd try to rig up a hidden switch with the appropriate resistors somewhere to take the place of the lock. I could find out the 'off' value pretty easily with a meter, I just need the 'on' resistance. Or if someone knows a reason my idea won't work that would be helpful too. Thanks...

I think I've read where someone has done that. You may want to hit the search button and see what you can find.

Possible source for alarm switch w keys
 

I got a new oem switch/2 keys from Auto Atlanta 5 or so years ago. The Porsche part was a perfect replacement.

They still show the switches on their site for $83 or so. Their site is confusing - do a search on their site for 'alarm keys'- that brought it up for me as it is listed as 'Alarm switch with keys'. Verify the part number. Call them if needed. ***********.com I believe.

I recall I ordered off their website, brand new part showed up in a week or so in genuine porsche part box and i was set. The 2 keys even have black rubber grips on them like modern keys.

Might be easier route.