I am having a very similar problem as the other posters here with my 2001 Monte Carlo SS.

I noticed first my keyless entry wouldn't work and the power door locks don't even work. When i turn the key to ACC all of my dashboard lights will come on but i cannot turn on the radio.

When I try to start the car nothing happens. The relay clicks but it doesn't try to start. I see the security light flashing and then a battery light then I get a service vehicle soon message.

I've tried leaving the key turned for about 30 minutes in case there was a security problem but that did not help.

I have the money to get some stuff replaced but I don't want to replace the key cylinder and then have this happen to me again.

Anyone found out the exact problem with this yet?

 

Did you find the problem. My 02 has failed to start twice and each time it reset with a little time lapse.

I read a bcm reset procedure here and tried it the second time but half way through it started after having sat with the key on for 12 minutes then off for 30 seconds(after start attempt)

I am wondering if an aftermarket alarm sytem will work, with the passlock disabled even though the bcm might have an intermitten fault?

 

Hey yall im having kinda the same issue but i believe my neutral saftey switch may have flipped when i rolled the car, my issue is i cant find it or any info stating where it is. Ive got the same car as the original poster (2001 ls 3400) otherwise what else could it be im getting no crank.

 

I have a 2001 Chevy Monte Carlo that won't turn over turned it off one day and wouldn't start changed the starter and the ignition and it still won't turn over there is no security light on what should I check