a/c one side of car colder than other

[jdodds]

i have a 2001 grand prixgt.it has the dual electronic temp. contol slide arms for interior a/c and heat one slide arm controls driver side and other pass side. the problem is the pass side blows out a colder air than the drivers side when both slide arms are in the coldest position is ther some way to adjust the heat a/c temp control module.