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Passlock- C4 1990 convertible

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Old 01-26-2013, 08:33 PM
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cornkobb
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Default Passlock- C4 1990 convertible

I was having probs with alarm going off. I went into both door panels and unplugged both passlock pigtails, now my power locks dont work. What can I do to bypass the passlock system? Is the VATS influnced by this or is it a seperate system, not affecting each other. I have a VATS bypass on standby if I need to use it. 1990 Corvette Convertible
Old 01-26-2013, 10:47 PM
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Hooked on Vettes
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The factory anti theft system has two separate parts to it.
The passkey is the part that reads the key pellet resistance of
the ignition key.

If it doesn't compare with the resistance the CCM was
programmed for the starter motor and fuel injector pulsing are disabled.

The factory alarm is set by using the power door lock switch.
With the door open you use the power door lock switch to lock the doors. When the doors are closed the alarm is set. The system then monitors the door ajar switches mounted on the back edge of the doors. On a coupe the hatch ajar switch is also monitored. If the alarm is triggered the horn is pulsed. To shut the alarm off you use the door key.

So if you set the alarm and it triggers for no reason the problem is most likely one of the door ajar switches.

Last edited by Hooked on Vettes; 01-26-2013 at 10:53 PM.
Old 01-26-2013, 11:10 PM
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cornkobb
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My door ajar switches are working. The dome lights come on and the engine runs fine. I just want to be able to bypass the door key switches. I unplugged the pig tails from inside the doors. Can a resistor be soldered in place?
Old 01-27-2013, 12:09 AM
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A switch is mounted on the back of each door key cylinder. When you turn the key to unlock the door the switch sends a ground signal to turn the alarm off. The switch has a connector plug with two wires. A
Green wire and a Black/White wire.

Here's a thread with a picture of the door disarm switch. This switch
has no connection with the power door locks.

http://forums.corvetteforum.com/1580140972-post4.html

Last edited by Hooked on Vettes; 01-27-2013 at 12:29 AM.
Old 01-27-2013, 10:48 AM
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markKlein
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Originally Posted by cornkobb
My door ajar switches are working. The dome lights come on and the engine runs fine. I just want to be able to bypass the door key switches. I unplugged the pig tails from inside the doors. Can a resistor be soldered in place?
VATS is not the alarm. They are separate systems.
Old 01-27-2013, 12:05 PM
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cornkobb
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Well crap! My manual's wiring schematic indicates by a dashed line that it ties into the power door locks!

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