Does this unit have an immobilizer system, and if so how do you re-set it?

Replaced a key fob with new and reprogrammed it w/o problem. Was running fine just before replacement, now the truck will not start, no fuel, etc.
 
 Doors lock/unlock, etc.
 No codes shown
 Cranks over fine
 No blown fuses

Any help would be appreciated!  No dealer within 100 mi.

Tom

Is the fob separate to the key?  The key has a unit in it that the ECM recognises.  If you've changed the key, the ECM needs to be reprogrammed to accept the replacement key.

The strange thing about this is that we had been operating the truck for nearly three years with keys made by a locksmith w/out a chip, all with no problems.  It was only when I ordered  a replacement fob from KeylessRide and did the reprogramming for the fob, that I ran into problems.

The auto transmission has also locked out, and into park.  Will use the over-ride button to get it unlocked.

Is the ECM user programmable, or does it need to be done by the dealer?  I have what I think is an original key. Reprogramming the fob with that key in the ignition does nothing to change the lock-out of systems on the truck.

The key does not have a chip in it.

The key does not have a chip in it.

OK, sorry, ours do in Europe.

Problem solved: 

Thought that I'd follow up on the earlier post. The US '99 GV does not have an immobilizer, even though the CD I have shows one. Had installed a new remote door key fob, which worked perfectly. Had no start problem afterward.

Found that when lowering the door lock module from under the dash for re-programming I had broken several wires in the inside of a multi-wire  harness. The harness was bound with plastic wire ties so tightly that my movement had caused the wires inside to break. 

Spliced the broken wires and now all is now well!