Duntov

My burglar alarm isn't working, and not sure where to begin. I was thinking at the rear switch (late 70 one) and see if it will have continuity. Not sure if the horn/trumpet will take straight 12 bolt or not. Any suggestions?

GunPowder

There is (as always) a good tech help at Willcox.

You can start with the electric diagram

http://repairs.willcoxcorvette.com/1...-alarm-system/

If the fuse is OK, the relais is often the culprit.

redrdstr72

Hi Duntov. (Duntov. That's good)

Yes, the alarm horn can take 12 volts but I wouldn't let it go long. It's a contact point that activates the sounding. If your system has been inoperative for some time, I'd be suspicious of several components, starting with the horn itself. I test horns with a spare 12 volt home alarm battery. Because of the designed location, alarm horns tended to corrode badly. Horns can be rebuilt/restored if originality is important to you. Be aware, restoration can be quite costly. If restoration is not important, an inexpensive std horn from your local auto parts store will work well.

My suggestion would be to qualify your horn first. Once you know you have a functioning horn, you can begin the systematic tracing of alarm workings such as key switch, wiring, relay, flasher switch and plunger switches. Your trial/error testing of the rest of the system will need the horn to sound as part of the process.

Hope this helps.