I recently bought a 2004 Silverado, 5.3L V8, LS1500, Ext. Cab, " as is". From day one I am seeing a message on the dash that says, " Service Tire Pressure Monitor", but none of the wheels have tire pressure sensors installed. Is there a way I can determine if someone swapped out the computer or the wheels? If the truck is supposed to have tire pressure sensors installed, do you think the service message will disappear if I install them?