Got a 1998 GMC T15 Jimmy V6 4 Door 4x4 that has the "security" light on steady as of Sunday. Today, it wouldn't start and the security light started blinking. I researched it online and then took apart the lower dash, wiggled the yellow passlock wire and then the car started fine. Light is still on solid, however. Research online seems to say the ignition cylinder needs to be replaced. do you guys agree with that assumption? Any other suggestions? Is this something I can do myself? Estimate on parts cost and labor? Thank you in advance.