1973 Anti-Theft Alarm Relay

[Roger S.]

The relay in my 1973 has 838 stamped onto the base and this number matches the last three digits of the relay shown in my copy of the AIM. In trying to find a spare relay I found a relay numbered 811 in the local junkyard. The relays once the cover is removed appear the same. Are they? If not what is the difference? Can they be interchanged?
Roger

[Joe L.]

Re: 1973 Anti-Theft Alarm Relay

Roger-----

I hope the number is "878"; there never was an "838" relay that I can find. Certainly, if there was, it was never used for the anti-theft horn relay for Corvettes.

GM #1115878 was the anti-theft horn relay used for 69-77 Corvettes. It was discontinued several years ago without supercession. GM #1115811 was the horn relay used for 1957-62 Chevrolet cars, including Corvettes. Under a supercessive part number, it is still available to this very day. However, the supercessive part number is not applicable to the anti-theft horn relay application. That does not bode well for the functionality in this application.

Notwithstanding the above, you could always try the relay in the anti-theft application. If it works, it works. If it doesn't, it doesn't.

[Roger S.]

Re: 1973 Anti-Theft Alarm Relay

I stand corrected, the relay is stamped 878. Is the horn relay a self latching relay also?
Roger

[Joe L.]

Re: 1973 Anti-Theft Alarm Relay

Roger-----

That I do not know.

[Terry M.]

Re: 1973 Anti-Theft Alarm Relay

I don't know about the horn relay being self-latching either, but think about it for a minute. Why would you want a horn relay to be self latching? One wants the horn on only when pressing on whatever actuates the horn.
That said, I don't think the alarm relay is self latching either. It is the wiring that connects to the relay that latches it on until the 12 volts from the alarm switch is removed by turning the alarm key.