security light

First try to relearn the key by following the instructions below

https://www.2carpros.com/articles/how-to-reset-a-security-system

If that doesn't work it may be the small wires that go from the ignition tumbler to the security system., they tend to break causing the system to not be able to recognize the key chip

The security light on my dash is on. The van has stopped running. We started having problems after we had a new key made at the dealer. What does that mean?

Hi:
The system is not recognizing the new key. Return it to the dealer.

joe

what does SECURITY on the instrument light mean?
after about 30 minutes of driving and I want to start the van the light SECURITY flashes and the van will not start.

you probably have a bad ignition cylinder and or ignition switch. your antitheft system is not reading the correct info intermittently and thinks its being stolen, thus nat starting. hope this helps

I changed my ignition and security light is flashing it won't start it wants to but won't kick over I changed the cylinder with a new pair o keys as well as the harness the cylinder sits in Someone said to do a relearn process but I don't know what that is or how to go about that

here's how to do it see pic

Your Question Edit Question
security light on 2001 chevy astro will not turn on. van won't start. had an o2 censor replaced a week before it died while I was driving. I refer to it dying as "ding ding dead" it powered off in a matter of seconds. and has not been revived since. garage says there is spark, and fuel line is fine. starter clicks repeatedly but no start. not the rotor, not the distributor cap. they tried resetting passlock (they said)

it cranks great, just doesn't start :( battery is good, garage didn't say connections were bad (they said they checked spark and that was good). what are these switches? if a clutch switch or neutral switch was bad...what would that entail?