Topic: alarm door switch help needed
in Forum: C3 Electrical
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As I move forward with getting this 72 on the road I am now ready to work on the interior. I find I need some help with the alarm and the door switches. I have already purchased the new switches. On the end there is a plug that takes 3 wires. (why 3 wires) The old switches were broken off but the plastic ends are still on the wires. I dont see a way to release the wires from this plastic connector. I dont want to break the ends. Any one know how to release these terminal ends? Also the hood switch which is the same as the door alarm switches only has 2 wires going to it. I am assuming that the alarm works by grounding the system. I know when the alarm key is turned on I get power to the horn. If I ground the horn it alarms! I have found a flasher and a relay in the storage jack area that I am sure will need to be replaced. They look like they are 39 yrs old! very rusted but still intact. Not sure what and when these relays and flasher should be energized or grounded but its time to find out! of course thats with the C3VR families help!
Thanks in advance for any help you can pass on.
Rodney
Thanks in advance for any help you can pass on.
Rodney

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Hey Rodney..dare I say post a pic of the connector..front and back..they are all different so if I see it I will know..I have some of those fancy pic tools for this purpose you can use.
Rich
Rich


My first parade at Carlisle 2010

Moderator
Duncanville, TX - USA
Joined: 11/8/2003
Posts: 20214
Vette(s): #1-1974 L-48 4spd Cp Med Red Metallic/Black deluxe int w/AC/tilt/tele./p/w-p/b/
Am-Fm/map light National/Regional/Chapter NCRS "Top Flight"
#2-1985 Bright Red/Carmine Cp.L-98/auto
Member: NCRS, NCRS Texas, Corvette Legends of Texas
The door pin switches are made to work both the interior lights and the alarm, so they have the ability to connect 3 wires. The hood alarm switch only works the alarm, therefore only two terminals.
The wires that go to the switches have tiny terminals that are snaked up thru the plastic slots on the switch, and then bent over. You'll need to carefully bend them straight on whats left of your old switches, and pull them out of the plastic. If you get them out without the ends breaking off, you've done good. Now just run them back into the new switch after threading the wires thru the hole in the hinge pillar first. The switch at the rear by the lock pillar will be the same..thread the wires thru the hole first, then attach them to the switch, and screw the switch into the hole.
The alarm relay should have 12v all the time once armed by the key switch on the rear panel. When the door or hood switch closes(makes contact/grounds), the relay closes, and sends the voltage to the flasher, which beeps the alarm horn on/off until you dis-able the system by turning the key in the rear panel.
hth
Adams' Apple 2011-01-09 11:29:42
The wires that go to the switches have tiny terminals that are snaked up thru the plastic slots on the switch, and then bent over. You'll need to carefully bend them straight on whats left of your old switches, and pull them out of the plastic. If you get them out without the ends breaking off, you've done good. Now just run them back into the new switch after threading the wires thru the hole in the hinge pillar first. The switch at the rear by the lock pillar will be the same..thread the wires thru the hole first, then attach them to the switch, and screw the switch into the hole.
The alarm relay should have 12v all the time once armed by the key switch on the rear panel. When the door or hood switch closes(makes contact/grounds), the relay closes, and sends the voltage to the flasher, which beeps the alarm horn on/off until you dis-able the system by turning the key in the rear panel.
hth

Joel Adams
C3VR Lifetime Member #56
My Link
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"Money can't buy happiness -- but somehow it's more comforting to cry in a CORVETTE than in a Kia"

Temple City, CA - USA
Joined: 10/3/2010
Posts: 365
Vette(s): 1969 Daytona Yellow. 350 / Automatic.
Thanks Rich and Joel. Not my question originally, but I have to replace a door ajar switch on my '69 and have been holding off until I could figure out the replacement connectors that are recommended by the parts houses. Now I get it.
I have been in your shoes....Lectric Limited has everything you'll need. I replaced all my harnesses and switches. Joel talked about bending those over and stuff. Be very carefull and take your time. I broke a couple of mine and had to replace them.
Lonnie, I already have to replace the ones on the passenger side as I found the end is already cut off. I found them at a few different venders. They look like all six which will do both sides comes together in one stamped out cutting, then you snip them off and install into the door switch once you have pulled the wires through. Rich and I talked about the circuitry on this last night and it looks as though the flasher supplies a ground. Is that what you found out? I have to order the ends and do more testing once i get them and install them.
Rodney
Rodney


Moderator
Duncanville, TX - USA
Joined: 11/8/2003
Posts: 20214
Vette(s): #1-1974 L-48 4spd Cp Med Red Metallic/Black deluxe int w/AC/tilt/tele./p/w-p/b/
Am-Fm/map light National/Regional/Chapter NCRS "Top Flight"
#2-1985 Bright Red/Carmine Cp.L-98/auto
Member: NCRS, NCRS Texas, Corvette Legends of Texas
Sorta...the pin switches actually provide the ground path, but it is 12v that travels thru the flasher...that's what makes the flasher work. Once the system is armed, there is 12v at the relay thu the horn, then thru the flasher. Once one or more of the pin switches closes, the relay latches closed, and stays that way until either the key switch in the rear panel is turned to disable the system, or the battery goes dead. It's the relay that continues to provide the ground from that point. You can shut the door or the hood, and the alarm will still sound. Once the key switch is turned(alarm OFF), then the relay looses it's 12v, and unlatches.
The circuitry in the flasher allows voltage thru(to ground) until the thermal spring gets hot, and it opens the contact. When it cools, it closes again. It does this pretty quickly on/off, thus causing the horn to beep beep.
The "anti-theft switch in engine compartment" in Bob's 77 diagram is prolly not present in the '68-'72 cars, but it may be...I've never actually looked to see. On the '73 up cars, it is the exact same switch that is used for the "headlight open" warning, and it is installed so that if the key switch in the fender is popped out, or otherwise disturbed(like cramming a screwdriver in it and turning), the alarm will sound.
It's really a fairly simple system...just a lot of wiring involved. Unless it's full of rust/corrosion, the relay rarely ever gives any problems...the flasher is a different story. It fails quite regularly, even if the alarm never sounds.
hth.
The circuitry in the flasher allows voltage thru(to ground) until the thermal spring gets hot, and it opens the contact. When it cools, it closes again. It does this pretty quickly on/off, thus causing the horn to beep beep.
The "anti-theft switch in engine compartment" in Bob's 77 diagram is prolly not present in the '68-'72 cars, but it may be...I've never actually looked to see. On the '73 up cars, it is the exact same switch that is used for the "headlight open" warning, and it is installed so that if the key switch in the fender is popped out, or otherwise disturbed(like cramming a screwdriver in it and turning), the alarm will sound.
It's really a fairly simple system...just a lot of wiring involved. Unless it's full of rust/corrosion, the relay rarely ever gives any problems...the flasher is a different story. It fails quite regularly, even if the alarm never sounds.
hth.
Joel Adams
C3VR Lifetime Member #56
My Link
(click for Texas-sized view!) NCRS
"Money can't buy happiness -- but somehow it's more comforting to cry in a CORVETTE than in a Kia"
Joel, with the flasher removed and the relay removed, the yellow wire that goes from the flasher to the horn base, when I ground this wire manually the alarm sounds. When I check this yellow wire with my power probe I find it to have a 12v signal. when i hit my power probe switch to ground the yellow wire, it alarms. Is this the way its supposed to operate. I havent gotten the jamb terminals yet to complete the system so I have everything unplugged and of course I have the battery disconnected when not working on it just to be sure nothing stays on! Hope this all makes sense.
Thanks
Rodney
Thanks
Rodney

Hey Rodney I thought I would post the diagram we talked about so there wouldn't be any confusion as to what is what..I traced the power wire..

Rich


My first parade at Carlisle 2010
in Forum: C3 Electrical
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