Thread: Infamous flashing security light

I have a weird issue with my 2002 Grand Prix GTP where I have to wait for the security light to stop flashing before I start the car. Now this issue may or may not be related to the other instances of this issue on the forum, so here's a little backstory:

I recently purchased this car used from a dealer/shop. The previous own tried to have BestBuy install an aftermarket security system for auto start, but the two security systems ended up fighting each other and so the car ended up bricked. The car was towed to this specialty shop where they immediately surmised the issue and removed the aftermarket security system. End of that story, the owner didn't want to pay for this repair and they left the car's title to the shop.

Unfortunately, this all somehow left the car with the security light issue. (I am not sure exactly how this happened if they just reset to the stock security system, but apparently BestBuy cut some wires somewhere and so the system isn't perfect.)

When I purchased the car, I was told that I would have to wait around a minute with the key in the run position for the security light to stop flashing. Great. I'm patient. I can handle one minute. Nope. I've had the car for a little while now and I have ended up waiting anywhere from 0 seconds to 20+ minutes for the security light to stop blinking. The shop said that standing outside the vehicle and locking/unlocking the doors with the key fob would help but I'm unsure if that has.

Additionally, I almost feel that this issue may be related to either temperature or time of day...for example in the mornings it usually stops blinking starts within a minute or so but in the afternoon I've waited over 10 minutes.

So, the TL;DR is above in bold although I would prefer the whole issue is known; now for the meat...

I've read up a lot on this issue. My car has PassKey III. I tried the 30-minute relearn procedure, but when I tried it in the morning the security stopped blinking right away and when I tried later that afternoon it kept blinking for 20+ minutes.

Basically, I'm hoping for a solution to this problem short of killing and bypassing the security altogether (also without buying expensive replacement parts), but if worst comes to worst I'm interested in understanding the procedure of bypassing security by cutting/splicing those yellow and black wires, wherever they may be.

Oh, I drove my car today and the after I got it started and I was driving the security light did stay on, which I believe is an indicator of an error of some kind.

Sorry for the long post, even now I may have forgotten details, so feel free to ask questions.

I highly suspect it could be either a bad ignition switch or chip in the key. The symptoms do seem to fit perfectly: the security light is slowly taking longer and longer to stop blinking and let me start. I'm getting the car checked with a diagnostics tool today, perhaps if there is an error code as to why the light stays on while I drive that could help.

If it is in the ignition, what part exactly would need to be replaced? Is the decoder in the ignition switch?

As for the security system as a whole, I suspect that the shop probably assumed (maybe incorrectly) that the security system just went funky (without further diagnosis of the issue). I want to try and call them up and get some more info.

Ok, so last weekend I ran a diagnostics tool on the car and got a DTC code of B2955 "Key code input is short to battery". So I was gonna go in behind the kick panel and check the wiring and also consider replacing some stuff, but this week I was just fiddling around and I RANDOMLY found the WEIRDEST solution to my problem: If I put in the key, turn to run, and while the security light is blinking I CUP MY HAND around the key and the ignition, the light stops blinking and the car starts fine. I have NO CLUE why that would fix it. But it does. It has worked instantly and I have been able to start the car as normal every single time this week. So for now, I'm not gonna go tearing the car apart, but search me as to why on EARTH this fixes it.

To anyone else who may have this issue and has found this thread: I would be SUPER interested in knowing what this technique does for you. Impala and BigBoost, thanks for the suggestions though!