My anti theft is locking up the ignition randomly!

Hey Terry... welcome to the forum :)

unfortunately i cannot answer your questions as we don't get the anti theft systems here NZ from the factory but if you go to www.supraforums.com and ask there i'm sure they will help out :)
or hopefully there is more usdm spec supra owners here that can help

good luck with it and if you get no luck at all i suggest getting an auto electrician to have a look at your car

ps. what do you mean it's locking the ignition randomly... not physically i would imagine but it won't de-immobilise i assume?