2004 Escalade Esv- Problem With Avc Setting On Fact Radio

CAn anyone help, i added 24inch rims on my 2004 escalade esv and everytime i turn the truck on i get a message " check tire monitor" days after i had intall 2 amplifiers and the hi-lo converters are connected after the boss factory amp. the problem that i am having is, everytime i select the AVC( audio volume control) option on the fact radio, my sound level goes crazy, goes up and down outof control, can this be because i changed the factory rims,
is there sensors on the tires ?:banghead: