Why is my security light flashing?
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Why is my security light flashing?
I replaced the dome light timer yesterday and now my dome lights and the hatch release switch in the drivers side door work (the switch on the passenger side door panel is missing) but now the security light on the dash is flashing for some reason. It never did that before but it's doing it now. When I got the car it didn't come with anything to turn the security system on and off and I figured that it didn't work because lots of things on the car didn't work. I'm down to just a couple things left to get working (the power mirrors and the cruise control), did replacing the dome light timer activate something on the security system? Are the hatch release switches in the door panels tied into the wiring for the security system and could the missing switch cause the problem? How do I get the security light to stop flashing when the car is off and parked (it turns off when I get in and turn the key on). Any help is appreciated.
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secretive about your car. What year coupe or vert? The Content Theft Deterrent is cause light to flash. There are tamper switches for the lock cylinders in the doors, they attach to lock cylinders. Since your not commenting about the interior light stay on. So you have a 50/50 chance of guessing the correct door 
Many times tamper switches will get fouled if some tries to "Slim Jim" the door.
Many times tamper switches will get fouled if some tries to "Slim Jim" the door.
Last edited by Kevova; Apr 6, 2018 at 03:23 PM.
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Joined: Apr 2016
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secretive about your car. What year coupe or vert? The Content Theft Deterrent is cause light to flash. There are tamper switches for the lock cylinders in the doors, they attach to lock cylinders. Since your not commenting about the interior light stay on. So you have a 50/50 chance of guessing the correct door Many times tamper switches will get fouled if some tries to "Slim Jim" the door.
Many times tamper switches will get fouled if some tries to "Slim Jim" the door.Last edited by TheGreek!; Apr 6, 2018 at 03:45 PM.
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The SECURITY light should only flash when a door is open. The flashing light means "a door is open, system is NOT armed".
If the light flashes with the doors closed, but IGN = OFF, one of the door switches is possibly corroded and causing the THEFT module to think a door is open. In an 85, the switch for the theft module is on the A-pillar. There are 3 wires on the driver side (theft, dome light, key buzzer) and 2 on the passenger side (theft and dome light).
To check the THEFT system operation:
Open both windows.
Close one of the doors.
With the other door open, lock that door with the POWER door locks.
SECURITY light should go SOLID.
Close the open door.
SECURITY light should go out a few seconds after the door closes. System is armed.
Reach in through the open window and unlock the door with the MANUAL lock. (If you use the power lock without opening the door, this disarms it. Start over).
Open the door. Alarm should sound. (Uses the car's horns.)
Silence alarm by turning outside key lock clockwise.
Repeat entire sequence for the other door.
To check the rear hatch:
Arm the alarm.
Reach in through the open window, open the center console and open the hatch with the yellow button.
Alarm should sound.
Disarm with either door outside key lock.
There are a lot of componets to the entire system. Switches, wiring, diode module, the horn system, and a couple of fuses including one hidden behind the radio. It wouldn't surprise me if your car has some issues that will affect the correct operation of the factory theft deterrent. But hey, maybe it will surprise us both and work as intended, designed, and expected.
The SECURITY light can NOT flash with the door closed, IGN = OFF. So start there, if it does.
If the light flashes with the doors closed, but IGN = OFF, one of the door switches is possibly corroded and causing the THEFT module to think a door is open. In an 85, the switch for the theft module is on the A-pillar. There are 3 wires on the driver side (theft, dome light, key buzzer) and 2 on the passenger side (theft and dome light).
To check the THEFT system operation:
Open both windows.
Close one of the doors.
With the other door open, lock that door with the POWER door locks.
SECURITY light should go SOLID.
Close the open door.
SECURITY light should go out a few seconds after the door closes. System is armed.
Reach in through the open window and unlock the door with the MANUAL lock. (If you use the power lock without opening the door, this disarms it. Start over).
Open the door. Alarm should sound. (Uses the car's horns.)
Silence alarm by turning outside key lock clockwise.
Repeat entire sequence for the other door.
To check the rear hatch:
Arm the alarm.
Reach in through the open window, open the center console and open the hatch with the yellow button.
Alarm should sound.
Disarm with either door outside key lock.
There are a lot of componets to the entire system. Switches, wiring, diode module, the horn system, and a couple of fuses including one hidden behind the radio. It wouldn't surprise me if your car has some issues that will affect the correct operation of the factory theft deterrent. But hey, maybe it will surprise us both and work as intended, designed, and expected.
The SECURITY light can NOT flash with the door closed, IGN = OFF. So start there, if it does.
