Seems the ignition switch is working correctly ( as well as PATS, but that would be a crank no start issue ), so next is on to the DTR ( digital Transmission Range ) sensor circuit.
2 tests for this.
1. Turn key to on, press and hold the brake and shift into Neutral, turn key to the start position.
If this is same symptoms :
2. time to check the circuit from the ignition switch to the starter motor relay in the fuse panel.
Pull the starter motor relay, the coil pin ( #86 ) will have power on it when the key is in the start position.
Use a meter to check for + VDC when the key is in the start position.
If you do not have + VDC here when the key is in the start position, either you have fuse # 102 blown or the DTR is no good.
Check at the DTR ( from 2006 EVTM )
Ign switch ( start position ) -> Red w/ light Blue stripe wire -> fuse panel ( no fuse here ) -> Dark Blue w/ Orange Stripe Wire -> DTR -> Tan w/ Red stripe wire -> Fuse panel ( to starter motor relay ).
With the truck off, you can meter for resistance or continuity from the Dark Blue w/ Orange stripe wire to the Tan w/ red stripe wire, and it should show < 50 ohms or continuity.
- If not, the DTR is no good, and needs to be cleaned or replaced.
Something is telling me the 2007 My had the starting diode added to the mix, so this might change things slightly in the layout. The starting diode is for when the key is turned to the start position and held for 1 sec, you can release the key and the truck will continue to keep the normally open contacts on the starter motor relay closed until the truck starts or until 5 ( 8 ?) seconds passes, at which point the normally open contacts return to that position.