Bfenty

Hey guys-

Just a thought as I'm fixing up my Vette. It's starting to look a lot better and I don't want to get it stolen. I hardly live in a heavy-crime area, but the 1985 doesn't have the VATS system, and I don't think it has much at all in the way of anti-theft devices.

SO-my question, is there an electrical line someplace that I could put on a switch that will keep the car from starting, but isn't obvious? I mean, if someone is really committed to stealing it I'm sure they still could but a simple hotwire wouldn't allow it to start without the switch being on.

First thought I have, is a line to where the injector fuses are that would keep power from the injectors. So it would crank and crank and never start. Would-be thief assumes it's just not going to start.

I know I could also install a full alarm system, but I honestly don't want to.

JoBy

* Cable to starter solenoid but that is easy to detect and bypass. ( And that is already there from 1984 also but it does not use the coded key )

* Power to ignition coil. Engine still gets fuel and could ruin sparkplugs.

* Power cable to fuel pump, can be heard.

* Power to injectors. You could add a relay behind the fuse panel.

Tom400CFI

You could install a switch in line for the injectors (though it would have to be a double pole switch)

You could install a switch in line in the wire that powers the coil.

You could install a switch in line in the wire that powers the start enable relay.

You could install a switch in the fuel pump power wire


Lots of options.

Bfenty

Thanks for all the suggestions! This one intrigues me. Where is the wire for the start enable relay?

Cruisinfanatic

The car does have a starter interrupt.
If the car is broken into, the alarm sounds and it won't start

JoBy

You have to lock it the right way and look at the "SAFETY" light. Flashing or steady.

Bfenty

I don't think the '85 does actually?

aklim

Paste a copy of the 10 most stolen cars in America on the windshield. Sorry but the C4 hasn't cracked that list in forever. Wouldn't worry about it. Not worth the hassle

JoBy

Open door => "SECURITY" is flashing.

Lock with central locking button => "SECURITY" without flashing.

Close door. Alarm is on.

Reach in and unlock the door and the alarm will go off.

Unlock with key to disarm.

That functionality is in the 1984 and I don't think they removed it in 1985.

Tom400CFI

I believe it's behind the center vents in the dash, on an '84.



I agree...but the "Vette Kart" candidate car I just bought was super cheap, B/C it had been stolen...then wrecked. So, it happens, I guess.

aklim

And an ugly guy can land a nympho hottie with a huge rack that owns a liquor store. Doesn't happen often but it too can happen. Hasn't happened to me and I am not ugly.

It can happen that it gets stolen but I don't think it is often enough for me to worry. Now if I owned something in the top 10 most stolen cars, sure.

Cruisinfanatic

you hit the power lock and shut the door. Can't be opened or started without the key

xrav22

Ya the alarm is prettey good and sounds loudly. What I read as a precaution if someone wanted to steal a early c4 they would stick a long screwdriver in the battery so it would go dead. No alarm after a few hours. That was back in the day. Now I doubt you have to worry. Mine is 85 also. I noticed a wire to a led (which was bad) mounted in my panel. When I replaced the led it was blinking as the wire was soldered onto one of the alarm connections. I put a small switch from frys next to the lighter so I can turn it on and off when I wish. I did not research where it was connected.

aklim

Pretty cool. Have you seen many alarms go off and what happens? People hardly look. I don't even bother to turn my head when an alarm goes off. Why? Pretty much anything can set it off. I can snort the engine a little in a parking garage and set off a few alarms. Granted my engine and exhaust is louder than most, it can still be an issue of people being desensitized by the hypersensitive alarms that sound for almost anything.

Cliff Harris

Your car has a TDS (Theft Deterrent System). If the door is opened while it's armed it will honk the horn and disable the starter via the starter enable relay (located behind the DIC in the center cluster).

Gibbles

Like others said, you have the same system my 84 has.
it does not have the special key later years use, and i'm thankful for that.
It's pretty basic, but the car will disable if the alarm is tripped.

It works much like the factory alarm on my S10, if the doors are unlocked with what the system thinks is the key, then it should disable.

On my car the alarm would trip when i unlocked the door with the key randomly.
Fixed that by cleaning the little key switch sensor.

It's not a perfect system, and i do wonder if a slim jim would bypass the alarm...

One thing that worries me is a joyride...

I can disable my car from starting or running through my ECM, but it was only a side effect of my engine mods.
New ECM can have several different programs loaded up at once, and i can switch them on the fly.

I have one memory bank loaded with a program that the fueling tables are zero'd out.
Sometimes for fun i switch the bank to shut the car off...

They also make battery disconnect relays, you could run a switch inside of the car to operate it.
​​​​​​​one option fpr a hidden switch is one of the head light dimmer switches for an old chevy truck, they mount on the floor...
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Bfenty

Some really cool suggestions in here

Cruisinfanatic

save your money. The theft deterrent system you have is all you need.

A Peter C4

Put full coverage insurance on it.

hemivett

Just helped a buddy get his, new to him, car running. PO couldnt get it started. 4 Kill switches! Like Peter C4 says. Insurance! I have an agreed value of 10k from Hagerty....$300 a year! Love Classic car Ins.! h