Hi I've got a 2003 sonoma zr2 and I can't seem to get any heat coming out of the floor vents no matter which setting I use on the dash, when I do put it to just floor it will only come out of the defrost? Any advice would be great thanks in advance
GMC Q&AAsk Your Question
2003 GMC Sonoma Question: Issue with getting heat to the floor vents?
Answer #1G. T. Service Center (4142 Answers) , Stephenville, TX - (254) 638-3236ProfessorG February 03, 2014, 17:36Master
Check and/or replace the mode door actuator. The defrost actuator opens and closes the floor, sorry.
Answer #2pushrod February 03, 2014, 17:44Master
Good chance you have a vacuum leak to heater control, under hood. Defalt setting is defrost!