Car is a 2005. So my switch was screwed up horrible. Mechanically failing, I tried to lube it, made it worse, could not turn it on after trying for 45 mins in 15 degree cold Saturday. So this morning I went to the local "you pull it" yard and got a complete switch from a Century. Went right in and got the Security light. I tried at least 12 times leaving the key on for 10 mins and the security word on the display would never go away. I tried 4 times in a row waiting 12-15 mins between and not trying to crank. Nothing, when I go to crank it the car has no response, like it cuts power. Is that the correct result of Security shut down? (Not a crank, no start, or start, then die right away like my VW Jetta does when key is not read correct sometimes. I even triesd cutting the yellow wire like a bunch of youtube videos showed, same result.Any idea or input of how things should act?

 

Not sure if this helps, but the ignition cylinder holds the passlock chip (and that cylinder, if you can get it to turn is real easy to pull out of the ignition switch which is the housing it sits in).
Now, when you pulled this, there should be a connector on the top of the switch housing (this is where that yellow wire and a black wire goes, these are for passlock). Did that connector get damaged when you made the swap? Proper way to not damage it is to remove the lock cylinder from the housing and then you can squeeze two tabs and lift the connector out of the housing.
If it got damaged, then it might be the cause of you issue (not making contact with the passlock chip).

Now as far as the relearn, you may need to put a batter charger on the car at this point. Here are steps I've used successfully for both PCM and ignition key relearns (you should be able to start from step 4 once you have a fully charged battery):

1. Disconnect battery
2. Install new computer
3. Reconnect battery
4. Put emergency brake on to disable daytime running lights (this step is required to help save battery power)
5. Make sure all doors trunk and hood are closed leave driver window down and reach in through the window
6. Try to start. If it doesn't start, leave the key in the ON position for 11 min on 97-03 cars and 15 min for 04 and newer cars. The security light should turn off after this amount of time.
7. Before proceeding, verify the security light is no longer on OR that the message center is no longer flashing the security message with the other messages it's cycling (such as battery).
8. Turn off ignition for 30 seconds
9. Try and start the car. It probably won't start on the first try. Repeat step 6 two more times.
10. If this doesn't work disconnect battery for 5 seconds and then try and start the car.

 

thanks for reply. The lock would turn. Long story short I broke the passlock deal. So I punted and put the entire used assembly with tumbler from the Buick in it. I was able to palce that passlock tab and plug the tumbler into it, etc. Since mine is an 05 your instructions said wait 15 mins. Everything i had read and videos watched said 10 mins. SO, maybe I need to wait 16-17 mins and see what happens. Also, I was leaving the door open the entire time. Does that screw things up? Thanks.

 

The important part about the wait time is for the security notice to go out (15 may be excessive, but it seems to work).

Leaving the door closed is to avoid further battery drain by having the interior lights on.

Make sure to recharge the battery again. My experience with the Monte is that it normally takes 3 attempts for the relearn to complete.

 

I got it going tonight. My fault was not turning the key to crank position on each cycle. I was just turning it on. Thanks