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77 Anti-Theft Alarm

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Old Jun 16, 2008 | 12:04 PM
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Default 77 Anti-Theft Alarm

I have a wiring diagram.

Now I need to locate the theft horn flasher, and the relay, so I can start troubleshooting.

Where are they located?

Update: Thanks everyone for the information.

My 77 is a late model, so the alarm sets from the door lock.

I found the flasher in the console under the shift lever. I didn't find the relay for sure, but it may have been the one with 5 wires in the console, behind the flasher.

The horn was located on the firewall, tucked in the fender near the steering column.

The problem turned out to be a bad connection to the horn, and thankfully not the lock switch, so I didn't have to remove the door panel, and work inside the door.

Last edited by fastcw; Jun 17, 2008 at 11:36 AM. Reason: Update
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Old Jun 16, 2008 | 12:31 PM
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Pretty sure it's the same as 78/79. Under the console forward of the shifter.
Shows the flasher, relay just behind/below it.
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Old Jun 16, 2008 | 01:30 PM
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The horn is on the driver's side rear next to the gas tank--over the muffler. Good luck.
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Old Jun 16, 2008 | 01:54 PM
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OK-I found the flasher where you indicated. But the relay is not there.

The flasher wires go to the drivers side of the console and disappear into a wire harness. I can't see where they go, but they must be going to the relay, wherever it is hidden.

Also, haven't been able to find the alarm horn. Does any one know where it is located?

Thanks.
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Old Jun 16, 2008 | 02:06 PM
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Originally Posted by fastcw
OK-I found the flasher where you indicated. But the relay is not there.

The flasher wires go to the drivers side of the console and disappear into a wire harness. I can't see where they go, but they must be going to the relay, wherever it is hidden.

Also, haven't been able to find the alarm horn. Does any one know where it is located?

Thanks.
read above
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Old Jun 16, 2008 | 02:56 PM
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Early production 77 used the same mounting location as the 76 rear of car. Mid to late production the alarm horn was mounted next to the steering column on firewall.
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Old Jun 16, 2008 | 05:06 PM
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Originally Posted by fastcw
OK-I found the flasher where you indicated. But the relay is not there.

Also, haven't been able to find the alarm horn. Does any one know where it is located?

Thanks.


As mentioned, the horn might be on the driver side firewell, tucked under the fender.
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Old Jun 16, 2008 | 06:24 PM
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OK--I have a relay in the location shown in the picture.

But it has 5 wires, all in one connector:
Black
Yellow
Orange
and:
Blue
Blue/white stripe

My wiring diagram shows 3 wires on the relay:
Black
White
Pink

Maybe the diagram I have is for an early 77, my 77 is a late model, with the alarm arming switch in the door lock.

Anyone know??

Thanks
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Old Jun 16, 2008 | 06:42 PM
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Check this site out. If you count the thumbnail pictures from right to left the alarm circuit thumbnail drawing should be the 31st. Click to enlarge. The left side of the diagram is for the alarm key in fender, the right side of the drawing is for the alarm key in drivers door.
Hope this helps.
Brian
http://www.europeancorvette.com/html...l_diagrams.htm
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