96 cav theft sys light

Just completed an engine change and had the battery our of the vehicle for about 2 weeks. Now engine cranks bur will not start. Plenty of fuel pressure. There is a Theft Sys light illuminated on the dash panel that we did not know existed. Unable to find any information on this anywhere. Did find a thread from a Clueless26 that had the same problem, ccent sent a reply to leave the key on for 20 minutes and see if the computer reset and to post a reply if it works......no reply posted.
Need to know if this will work or if there is anything else to try. This is my step Daughters car and she is using my Bonneville till we get it running. Want my car back...please help!

I had the same problem as well, I have a 96 cavi and here is what GM garage did to fix my prob. I had my factory tape player go out and i bought a new one from a junk yard, and when I installed it that blasted light came on. Well I got mad cursed alot and finally broke down and took it to a GM dealer repair shop. he had to reset the computer and it cost me $42.76 after taxes. Now this worked for mine but just in case before you spend out that kind of money I would ask a dealer first if they think this would work for you. I hope that this helped you even a little bit I know it worked for me :grinyes:

i had a 97 and the same problem. there was a small little black buttom under the dash like directly below the stearing wheel they called it a vallay switch for the alarm. they pushed it and it was fine. maybe there is one on your also.

yeah,these ecu's(computer) are weird in these cars,they are not just "plug-n-play".any time you change the ecu or the engine & use same ecu,you have to get the ecu reprogramed at the dealer,otherwise it will usually start for about one second and shut-down and the theft sys. light will flash & stay on.

yeah,these ecu's(computer) are weird in these cars,they are not just "plug-n-play".any time you change the ecu or the engine & use same ecu,you have to get the ecu reprogramed at the dealer,otherwise it will usually start for about one second and shut-down and the theft sys. light will flash & stay on.


Is there anyway to disable this feature? Also why does this only happen sometimes? It happens sometimes to me and on other days it starts and runs just fine. :confused:

Is there anyway to disable this feature? Also why does this only happen sometimes? It happens sometimes to me and on other days it starts and runs just fine. :confused:
i dont think that there is any way to disable it. sounds like you might have another problem,or maybe a short in the ecu wires or even a bad ecu.