Security light coming on...

[TCHRISD]

I have a '96 LSS . When I'm driving this vehicle the security light will come on randomly. It doesn't seem to effect the driving of the car but I am wondering why this is happening?

[Tech II]

What kind of ignition key do you have? Black resistor chip or PK3 stamped on it?

[TCHRISD]

Originally Posted by Tech II

What kind of ignition key do you have? Black resistor chip or PK3 stamped on it?

Iti is the black resistor chip w/ the little lateral metal piece in a black square-ish part.
It doesn't have a problem starting or running but the light is on just about all the time now.

[Tech II]

Well, there are two things that I can thing of......your ignition lock cylinder or one of your door locks.....

While you are driving, do any of the door locks, lock/unlock while going over a bump(this may be accompanied by the interior lights coming on, and the SECURITY LIGHT comes on as well)?....this can be caused by a faulty door handle switch.....

The other possibility is the ignition lock cylinder(most likely)......there are two small white wires that go to it(this is the electrical circuit that is used to "read" the "R-value" of the resistance on the key).....

When you go to start your car, if the resistance is wrong or can't be read, the SECURITY LIGHT STAYS ON(USUALLY GOES OUT AFTER 3 SECONDS FROM THE TIME YOU TURN YOUR KEY ON)......If that happens, the car won't even crank.....

If it happens AFTER the car has started, your car will set a code(won't turn on the CE light)......what happens now is, your PassKey security system has gone into a backup mode......even though the light is on, or later goes off, your car will still continue to start......but the PassKey system is no longer working.....what happens is, one of those two wires going to the lock cylinder, may be broken INSIDE the insulation, so it is making intermittant contact as you turn the key......when the circuit is broken, the light comes on.....

Now as long as this has happened AFTER starting the car, there is no problem.....however, if for some reason your battery went dead, or it had to be disconnected for some reason, this resets the backup mode.....if you try to start the car, and the problem is there BEFORE ATTEMPTING TO START THE CAR, now it won't even crank....so if this is your problem, make sure you don't disconnect the battery.....

A shop would have to scan the vehicle for Theft Deterrant codes......they would also have to check the integrity of those wires up to the lock cylinder....

[TCHRISD]

My drivers side door does have a locking problem but it's been that way for a long time. I have noticed that sometimes is wont start on first try but does immediately after

[Tech II]

When you say it won't start, do you mean it cranks but doesn't fire, or it doesn't crank at all?

[TCHRISD]

Originally Posted by Tech II

When you say it won't start, do you mean it cranks but doesn't fire, or it doesn't crank at all?

When it does that, it won't crank at all. Then I try a second later and it cranks fine.

[Tech II]

Doesn't sound like a PassKey problem, because if it was, it wouldn't restart immediately.....there is usually a lockout timer associated with it, that is usually 3 minutes....

Try this,,,,,every timetime you go to start your car, just turn key to "on", don't try to crank it.....watch SECURITY light....should go out after 3 seconds....if it does, then start car......if it doesn't crank, check connections at starter......the other possibility is a bad starter enable relay....

If the light doesn't go out after 3 seconds, and then starter doesn't crank, then you have a Passkey problem.....

The only way you can check the door switches for a SECURITY problem, is with a GM scan tool, unfortunately.....

[TCHRISD]

Originally Posted by Tech II

Doesn't sound like a PassKey problem, because if it was, it wouldn't restart immediately.....there is usually a lockout timer associated with it, that is usually 3 minutes....

Try this,,,,,every timetime you go to start your car, just turn key to "on", don't try to crank it.....watch SECURITY light....should go out after 3 seconds....if it does, then start car......if it doesn't crank, check connections at starter......the other possibility is a bad starter enable relay....

If the light doesn't go out after 3 seconds, and then starter doesn't crank, then you have a Passkey problem.....

The only way you can check the door switches for a SECURITY problem, is with a GM scan tool, unfortunately.....

OK.
I changed the lock acuator on my driver door about a year ago. When I went to plug in the wire harness I must have damaged one of the female side inserts. Now my driver door will not lock or unlock when the button is pushed and the radio will not turn off automatically when I take the keys out and open the door. But all the other door locks work and if i have passengers when they get out of their door the radio will go off. Also the cabin lights wont come on when I open just the driver door to enter/exit.
But that's been like that for a year and this security thing has been happening for a couple weeks.

[TCHRISD]

Originally Posted by Tech II

Well, there are two things that I can thing of......your ignition lock cylinder or one of your door locks.....

While you are driving, do any of the door locks, lock/unlock while going over a bump(this may be accompanied by the interior lights coming on, and the SECURITY LIGHT comes on as well)?....this can be caused by a faulty door handle switch.....

The other possibility is the ignition lock cylinder(most likely)......there are two small white wires that go to it(this is the electrical circuit that is used to "read" the "R-value" of the resistance on the key).....

When you go to start your car, if the resistance is wrong or can't be read, the SECURITY LIGHT STAYS ON(USUALLY GOES OUT AFTER 3 SECONDS FROM THE TIME YOU TURN YOUR KEY ON)......If that happens, the car won't even crank.....

If it happens AFTER the car has started, your car will set a code(won't turn on the CE light)......what happens now is, your PassKey security system has gone into a backup mode......even though the light is on, or later goes off, your car will still continue to start......but the PassKey system is no longer working.....what happens is, one of those two wires going to the lock cylinder, may be broken INSIDE the insulation, so it is making intermittant contact as you turn the key......when the circuit is broken, the light comes on.....

Now as long as this has happened AFTER starting the car, there is no problem.....however, if for some reason your battery went dead, or it had to be disconnected for some reason, this resets the backup mode.....if you try to start the car, and the problem is there BEFORE ATTEMPTING TO START THE CAR, now it won't even crank....so if this is your problem, make sure you don't disconnect the battery.....

A shop would have to scan the vehicle for Theft Deterrant codes......they would also have to check the integrity of those wires up to the lock cylinder....

I think this is the problem cuz it's getting worse. Won't start the 1st or 2nd time but eventually starts. Is this hard to get to to check out the wires?