okso i have a 2002 2 dr 4x4 blazer that i need help with. i tried asking the guys on the blazer forum what to do but i got no response. so here it is...

ok so my turn signal/brights/wiper switch went bad.. so i went to the junk yard got one from the same modelyear and every thing, changed it out with a couple hours a little difficulty but i got it in and every thing... it works great!.. except my security light is now ON. not flashing. just ON all the time. and my car will not start i know it wants to but the security is holding it back..
it feels like when i bought a new key for my grand prix that wasnt micro chipped. it will turn over run for about a second and shut off...

i dissconected my battery and let it sit for a good amount of time came back to it and tried starting but the same thing happened..

please help.

 

There are several reasons the VATS system will prevent the car from starting. They range from a grimy key to dirty contacts in the ignition cylinder to broken wires or a bad BCM. Do a search on "VATS" to find plenty of advice on troubleshooting.

 

Your blazer has Passlock 2, not vats. Try leaving the key on in the ignition position for 10-15 mins. That is the reset for when it gets tripped. If that doesn't work maybe there is another issue from the swap you did.

 

Sorry, VATS is an acronym for Vehicle Anti Theft System and applies to both the PASS-Key and PASS-Lock variations.

You can tell the difference because PASS-Key uses ignition keys with a resistor pellet in the key shaft whereas PASS-Lock uses ordinary keys and has its sensor inside the ignition cylinder. If you have a resistor pellet in your key, the bypass procedure used for 4th gen f-bodies will work. If not, the PASS-Lock system is much easier to bypass since you don't have to fuss with resistors.