Quick 81 Theft Deterrent Question
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Quick 81 Theft Deterrent Question
I have an 81 and from what I could determine from my research, the theft deterrent was standard on 81s.
However, most of the posts refer to using the power locks to arm it.
I, however, have manual locks.
So my question is, does the 81 with manual locks have the alarm?
How do I determine if it is on my car?
I've never had it go off it it is there, so I'm wondering if it was removed when the CCC was removed, when the previous owner installed a crate motor.
Is there a definitive component/wiring I can check the existence of to determine if it is still in operation in my vehicle?
Thanks in advance for any info.
However, most of the posts refer to using the power locks to arm it.
I, however, have manual locks.
So my question is, does the 81 with manual locks have the alarm?
How do I determine if it is on my car?
I've never had it go off it it is there, so I'm wondering if it was removed when the CCC was removed, when the previous owner installed a crate motor.
Is there a definitive component/wiring I can check the existence of to determine if it is still in operation in my vehicle?
Thanks in advance for any info.
Le Mans Master
Joined: Aug 2010
Posts: 5,339
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From: Central Texas
Check in the jack storage area under the rear passenger side storage compartment. The "black box" for the alarm system should be to the front of that compartment. It should have about 11 wires connected to it. A light blue wire is a give away. That's the sensor input wire.
Le Mans Master
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From: Boca Raton Florida
I know the 81 with mechanical locks had the alarm at least as an option, but don't know if it was standard, might have been. None of the drawings in my book mention it as an option. It arms when you lock the door with the key, disarms same way. You can get a good alarm pretty cheap and its nt very hard to install. If your car does have the alarm its pretty easy to delete it and replace it with aftermarket like a Viper system. You can even add electric locks pretty easily.
Race Director
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From: Shamong, NJ
ALL 81 Corvette came standard with an alarm system, that included a starter interrupt feature.
On 81's without power locks, the alarm is armed by locking the doors with the push buttons. When the last door is closed, the alarm is armed. The alarm is disarmed by unlocking a door with a key. A tripped alarm can be silenced by putting the key in the ignition and turning it to the run position.
On 81's without power locks, the alarm is armed by locking the doors with the push buttons. When the last door is closed, the alarm is armed. The alarm is disarmed by unlocking a door with a key. A tripped alarm can be silenced by putting the key in the ignition and turning it to the run position.
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Thanks for the info... so it looks like I have the alarm, but it is not functioning.
Does anyone actually use the OEM alarm or is it pretty worthless?
I'm just wondering if it is worth troubleshooting.
What other options/suggestions are there for car security?
Thanks for any info.
Does anyone actually use the OEM alarm or is it pretty worthless?
I'm just wondering if it is worth troubleshooting.
What other options/suggestions are there for car security?
Thanks for any info.
Le Mans Master
Joined: Aug 2010
Posts: 5,339
Likes: 546
From: Central Texas
I think the factory system was a good one. There is just so much more out there as far as aftermarket alarm systems today. Also the parts for a 31 year old system might not be readily available.
I tied in my factory sensors via the blue wire to an aftermarket alarm system. I was planning on upgrading anyway so I didn't troubleshoot the factory system. I just made sure the inputs that I wanted were working correctly.
I tied in my factory sensors via the blue wire to an aftermarket alarm system. I was planning on upgrading anyway so I didn't troubleshoot the factory system. I just made sure the inputs that I wanted were working correctly.
Race Director
Joined: Oct 2000
Posts: 12,655
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From: Shamong, NJ
You should also be able to trip the alarm, by removing a t-top, or opening the hood, as they are both tied into the alarm system.
Does anyone actually use the OEM alarm or is it pretty worthless?
The factory alarm in the 81, isn't really a bad system. For 81, the factory alarm included a starter interrupt feature. 81 was the first year to use it, and basically it prevented the car from being started, if the alarm was tripped.
On 80 and earlier Corvettes, all the alarm did was blow a horn.
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That sounds like a great plan.
I saw a Viper on amazon for about $100 that looks pretty effective.
http://www.amazon.com/Viper-Responde...52/ref=lh_ni_t
Thoughts?
Where, specifically, did you pick up the existing wiring in the car from?
Did you splice into the wiring harness at the Theft Deterrent Control Module? Where is that located on the vehicle? I have the wiring diagram, but it's hard to determine where those components physically sit in the car.
I'm guessing the lt blue wire, when active, means at least one of the trip sensors in the car has been activated - correct?
I saw a Viper on amazon for about $100 that looks pretty effective.
http://www.amazon.com/Viper-Responde...52/ref=lh_ni_t
Thoughts?
Where, specifically, did you pick up the existing wiring in the car from?
Did you splice into the wiring harness at the Theft Deterrent Control Module? Where is that located on the vehicle? I have the wiring diagram, but it's hard to determine where those components physically sit in the car.
I'm guessing the lt blue wire, when active, means at least one of the trip sensors in the car has been activated - correct?
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I have been studying the 81 wiring diagram for the theft deterrent system and had some questions for anyone who has tapped into the existing wiring for an aftermarket install
(All references are to the 81 wiring diagram)
1) Where is the t-top trip (lt blue?) wire? I didn't see any wire that ended up in something called "removable top". Perhaps it is the one labeled "Deterrent Switches (mech locks)"? If not, which wire/signal indicates a top removal and what exactly are the "Deterrent Switches (mech locks)" that connect to the control module?
2) I'm guessing that the "Anti-theft Control Switch" is what arms the system, correct?
3) I see lt blue wires going to the two door switches, presumably to indicate that a door has been opened - what is the lt blue wire going to the "anti-theft protect sw" for?
4) What would be the best place to tap into both door locks, both tops, and the hood individual lt blue sensor wires (as opposed to the main one that connects to the control module) so an aftermarket alarm could identify which of the 5 sensors had been tripped?
5) Least important question... why does the theft deterrent module have a connection to the radio???
Thanks for any guidance.
(All references are to the 81 wiring diagram)
1) Where is the t-top trip (lt blue?) wire? I didn't see any wire that ended up in something called "removable top". Perhaps it is the one labeled "Deterrent Switches (mech locks)"? If not, which wire/signal indicates a top removal and what exactly are the "Deterrent Switches (mech locks)" that connect to the control module?
2) I'm guessing that the "Anti-theft Control Switch" is what arms the system, correct?
3) I see lt blue wires going to the two door switches, presumably to indicate that a door has been opened - what is the lt blue wire going to the "anti-theft protect sw" for?
4) What would be the best place to tap into both door locks, both tops, and the hood individual lt blue sensor wires (as opposed to the main one that connects to the control module) so an aftermarket alarm could identify which of the 5 sensors had been tripped?
5) Least important question... why does the theft deterrent module have a connection to the radio???
Thanks for any guidance.
Team Owner
Joined: Jun 2000
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From: Southbound
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Read through your owner's manual; it explains the factory alarm system installed on all 81s and how you arm it/disarm it.
Purchase the assembly instruction manual and take a look at the factory door switches, door lock cylinders, halo panel top hardware, the hood switch, and the anti-theft relays. That shows you the factory system.
Once you know what you have, then you can decide if the aftermarket system is worth the cost.
Purchase the assembly instruction manual and take a look at the factory door switches, door lock cylinders, halo panel top hardware, the hood switch, and the anti-theft relays. That shows you the factory system.
Once you know what you have, then you can decide if the aftermarket system is worth the cost.
Le Mans Master
Joined: Jan 2006
Posts: 9,192
Likes: 27
From: Boca Raton Florida
I have been studying the 81 wiring diagram for the theft deterrent system and had some questions for anyone who has tapped into the existing wiring for an aftermarket install
(All references are to the 81 wiring diagram)
1) Where is the t-top trip (lt blue?) wire? Inside the B Pillar attached to the receiver for the T-Top locator pin. I didn't see any wire that ended up in something called "removable top". Perhaps it is the one labeled "Deterrent Switches (mech locks)"? If not, which wire/signal indicates a top removal and what exactly are the "Deterrent Switches (mech locks)" that connect to the control module?
2) I'm guessing that the "Anti-theft Control Switch" is what arms the system, correct? My drawing says Door Key Switch for arm/disarm
3) I see lt blue wires going to the two door switches, presumably to indicate that a door has been opened - what is the lt blue wire going to the "anti-theft protect sw" for? Tamper switch on the door lock
4) What would be the best place to tap into both door locks, both tops, and the hood individual lt blue sensor wires (as opposed to the main one that connects to the control module) so an aftermarket alarm could identify which of the 5 sensors had been tripped? If your replacing the existing alarm you can access most of the wireing at the old alarm location. All the alarm trip wires are tied together, so you would need to seperate them in order for the new alarm to indicate what Zone tripped. I concidered this and kept just 1 zone.
5) Least important question... why does the theft deterrent module have a connection to the radio??? No idea why the radio power was routed to the alarm connector, it doesn't do anything
Thanks for any guidance.
(All references are to the 81 wiring diagram)
1) Where is the t-top trip (lt blue?) wire? Inside the B Pillar attached to the receiver for the T-Top locator pin. I didn't see any wire that ended up in something called "removable top". Perhaps it is the one labeled "Deterrent Switches (mech locks)"? If not, which wire/signal indicates a top removal and what exactly are the "Deterrent Switches (mech locks)" that connect to the control module?
2) I'm guessing that the "Anti-theft Control Switch" is what arms the system, correct? My drawing says Door Key Switch for arm/disarm
3) I see lt blue wires going to the two door switches, presumably to indicate that a door has been opened - what is the lt blue wire going to the "anti-theft protect sw" for? Tamper switch on the door lock
4) What would be the best place to tap into both door locks, both tops, and the hood individual lt blue sensor wires (as opposed to the main one that connects to the control module) so an aftermarket alarm could identify which of the 5 sensors had been tripped? If your replacing the existing alarm you can access most of the wireing at the old alarm location. All the alarm trip wires are tied together, so you would need to seperate them in order for the new alarm to indicate what Zone tripped. I concidered this and kept just 1 zone.
5) Least important question... why does the theft deterrent module have a connection to the radio??? No idea why the radio power was routed to the alarm connector, it doesn't do anything
Thanks for any guidance.
http://forums.corvetteforum.com/c3-t...oor-locks.html