1974 Anti-theft system
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8th Gear
Joined: Feb 2009
Posts: 8
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From: Newnan Georgia
1974 Anti-theft system
I'm trying to get my anti-theft system working again, and have replaced both of the door ajar switches and the hood switch, but the 1974 chevy manual wiring diagram I have shows a anti-theft warning switch in the system. I searched Eckler's on-line catalog for this switch and they list the headlight door switch to be a anti-theft/headlight door warning switch, but the wiring diagram shows this switch only to control the headlight door warning lamp. Does anyone have a clue where this anti-theft warning switch is located?
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Joined: Jun 2006
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From: Monroe Washington
I have a 1976 coupe with the antitheft key switch mounted in the left fender. The "warning" switch gets mounted at the rear of the key switch. As I understand it, this warning switch is like a tamper switch. If the key switch is dislodged, the warning switch activates the alarm.
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From: mount holly NC
2025 c3 ('74-'82) of the Year Finalist - Unmodified
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It is the same switch that is used for the headlights. Here's a picture from 'Willcox's 1974 --Repair and Install help site--listed under alarm switches. PG.
Thread Starter
8th Gear
Joined: Feb 2009
Posts: 8
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From: Newnan Georgia
1974 Anti-theft system (revisited)
I do have the model with the key switch mounted on the left front fender and have removed the key switch, but there is no warning/tamper switch mounted on the back of the key switch. I also tested the anti-theft system with the headlight door switches open and closed, and the system would not set either way, as soon as I turn the anti-theft key the alarm horn goes off. The headlight door switches only seem to control the headlight warning lamp on the dash. So I'm still at a loss to where the anti-theft warning switch is located in the system. I appreciate the responses. Does anyone else have any suggestions?
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I also tested the anti-theft system with the headlight door switches open and closed, and the system would not set either way, as soon as I turn the anti-theft key the alarm horn goes off. The headlight door switches only seem to control the headlight warning lamp on the dash.
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Thread Starter
8th Gear
Joined: Feb 2009
Posts: 8
Likes: 0
From: Newnan Georgia
1974 Anti-theft system (revisited again)
OK, I went back and looked at the fender key alarm switch and I found the alarm warning switch and wire connector had been either disconnected or unscrewed from the mounting bracket and was hanging down (out of sight). Hence the problem with the alarm not setting.
Thanks for all the help guys!! Happy Vetting!
Thanks for all the help guys!! Happy Vetting!
