[aussiblue]

Did you actually swap fuses and relays while originally testing; or did you just pull and check each one? What did you actually do? To me, it sound like the Smartshield as seen what it has interpreted as an attempt to hotwire the ignition and immobilised the ute.

Note also the Smartshield system can be confused by stray RF signals and things like nearby mains transformers, power generators, battery chargers and radio transceivers can stop it working as can metallic window tint (blocks the signal from the fob). Has anything electronic (sat nav, GPS, mobile phone, sat radio etc) that could be interfering with the fob signal been put inside the cab or on the key ring of the fob and is there anything nearby that could be generating RF interference. If the utes in your shed turn everything else in the shed off. I have a Repco Jump Starter that cause these sort of issue while it is charging (it also sets off my shed and car alarms).