Iirc = if I remember correctly
Au became smart shield after 6-99 before that it was smart lock which is a different system ie can’t use the
bem
Did you program remote to your vehicle and try it- reason for this is only incase vehicle has a aftermarket alarm or immobiliser hidden somewhere that activated when you disconnected battery
You are not going to start vehicle while smart shield light is flashing- should turn off when ignition is turned on - as mentioned it has a chip in key and key reader around where key goes in - also as mentioned make sure you haven’t mixed up keys from other vehicle
Smart shield key will have a slot where key ring goes half way across if genuine key
Have you carried out a parameter reset yet ?
What was actually wrong with tail lights ?
Don’t use forscan myself but does it show any other codes in the
pcm ?
Do you have power at the green with yellow wire at the interior light?