security light/ occasional no start
 

Started a few days ago. 2000 zr2. Sat.stopped at the store, came out no start. Turned over, fired then died. After 10 minutes or so started right up. Same today, went to store came out no start. Waited and it started. Thought maybe Ign. module getting hot so I replaced that.
Started it up, security light was on and stayed on. Shut it off, restarted and no light. Any ideas? ign. switch maybe?

If the security light stays on, you're looking at a Passlock issue. Passlock will allow the start but the BCM will command the PCM to shut off the injectors and it will stall within a very few seconds. Could be a communication problem or the sensor is not recognizing the key. Need to read the body codes, (powertrain scanner will not access them).

so how do I read them?

Need to find someone with a high dollar scanner that can access them.

Captain, I bought a new cylinder, Installed it and nothing, wouldnt even turn over, no security light but everything else worked. Was hearing a clicking from under the dash( picture on another post) pulled the panels and found a viper system. Unplugged the longest connecter which had a fuse inline and the clicking stopped. Turned the key and she fired right up. Let it run for 20 minute or so, shut it off and restarted. Security lights seem normal. Thinking the viper was the problem all a long, Fingers crossed. Will report back in a few days

Cool! Good job. Aftermarket security systems don't get along very well with Passlock. Basically people install them to get the key FOB so they have keyless entry and or remote start. Passlock is way more sophisticated than any aftermarket system. The lock cylinder is not what "reads" the key. There is a sensor further inside the lock cylinder opening.

What have I learned? Hate car alarms, always have, always will

I hope i'm not hijacking this thread but have either of you seen a GM security feature where you must click left directional before turning the key otherwise the horn honks with no start? The elderly, one owner, I bough my blazer from said he had it from the factory.

Now thats funny, yours does this?

Newguy, lesson learned, A+


Madmaxxed, Something wrong there. If it has an aftermarket security or remote start system, it's very likely that's the problem. Might want to remove it before it causes a more serious issue;)


When I see or hear an alarm going off, my standard reply is, "Buy a house in a good neighborhood, and you wouldn't need that thing". ;)