I have a 73 but i have no alarm key on the rear of car. It was built September 1st of 1972 , could it be that it being a early produced 73 it didnt come with a alarm? As i understand it was standard in 73 ? thanks for any help.

Stranger things have happened. My 73 was produced in January and it has a factory installed removeable back window, which was not available in 73. Go figure. I have a close friend who retired many years ago from GM. He says they will use up their stock of parts on the next model. No idea but my guess is that yours came without the alarm. Only an assumption and we know where that leads.

My '73 was produced in Dec '72 and has the standard alarm in the rear panel and no removable window. ................Regarding the alarm, do you have any of the alarm components ?? Look for two wires coming out of the harness above the license plate, the alarm horn itself up in the drivers side rear fender. There is also a silver rectangular relay back in the jack compartment. You have to remove the storage tray and look back towards the front of the car, it's kinda tucked in there. While it is possible that a Sept, 72 car was produced without one, a lot of people disconnected these early alarms because they were a pain. If you have some of the other components listed above or the remnants of the connections in the wiring harness it is very possible the hole for the alarm got filled in and painted over. ..................Regarding the rear window, again possible, but there was also an early GM Tech Bulliten regarding leaking rear windows and I believe a removable rear window could be retro fit into the '73 opening if you added the right components from an earlier car. Does you car also have the rear storage tray to store the removable rear window ??

Ok thanks for the help. I will look to see if any signs of it it being installed and later removed as you mentioned. Currently im offshore on a drilling rig so it will have to wait until i go home in Jan. 

|UPDATED|12/13/2015 5:26:50 PM (AZT)|/UPDATED|

Hello, I did get your earlier PM, and I did respond to it. Another easy item to check for is the alarm switch located on the rear passenger side under the hood. It should have the letters "sx" stamped on it. This switch is for alarm activation if the hood is opened while the alarm is armed. It has no other purpose. If it is present, car had an alarm. Which I am positive that it left the factory with one. Please let me know if you have any questions about your 73 convertible. Be safe out there on that rig my man!

Hey Tooch, good to hear from you. Is the alarm all good on your car ?? I've got mine working but I'm on the hunt for an original SX switch for my drivers side door. The service rep. part I got to get it working is blank, no stamp. How did your battery cable project turn out ??

|UPDATED|12/14/2015 12:20:47 PM (AZT)|/UPDATED|

Vman73, My alarm is working fine right now! (Knock on wood!). You won't find a vendor that sells the switches with the "sx". Even the gm packaged ones won't have it on them. You'll need to try to find them used on eBay. Mine are the new ones without the stamping. I'll send you a private email about this. My battery box was in pretty bad shape, but I did get it repaired pretty well. Looks pretty nice under the car, but by no means perfect. 10 times better than it was and I now have an oem negative cable with the correct grommet.

Lectric Limited  has the SX pin switches, for anyone that is interested. 




|UPDATED|12/14/2015 8:26:37 PM (AZT)|/UPDATED|

pt I believe that Lectric Limited switch was used up to 72. My 73 needed the switch pictured here. I haven't seen this type with the "sx" sold by any vendor.

|UPDATED|12/15/2015 12:11:49 AM (AZT)|/UPDATED|

Pretty amazing how many different versions of that switch I seen, thanks GM !! Tooch is right, the one shown in his pic with the GM bag is the one we need for the '73 door adjar/alarm switch. I bought the same replacement for my driver's side, works great, no SX. The one in Joel's pic is very simular to the original one I have for my hood contact, a little longer but very close. I was able to salvage mine by installing a new set of contacts. Keeping my eye on EBay so I can pay way too much for a 42 year old used switch and hope it works, LOL !!