my heater works but when i push the defroster it switches to vent what do i do to fix this/
Dec 15, 2008 at 8:15 AM
JACOBANDNICKOLAS
✓Experienced Mechanic
110,246 POSTS
Hi:
There are vent doors in the HVAC duct work that are actuated by vacuum. You will need to check for a vacuum leak at the switch or see if you can hear a hiss coming from anywhere under the dash.