2002 Chevy S-10 Heater Modes

2002 CHEVROLET S-10

89,000 MILES • 6 CYL • 4WD • AUTOMATIC

GUVIC

MEMBER
3 POSTS

Hi:
My heater modes are not right. I noticed this last winter when defrost was very weak. Here is what is happening in all 4 modes:
1) When selector is in all vent mode, dash vent force is good and there is some moderate floor air.
2) When in all floor mode dash vent force is less and floor force is also less
3) When in defrost and floor mode small floor force, small dash vent force and small floor force
4) When in all defrost there is small defrost force no floor and smaller dash vent force.
It is working very funny. Can you help me?

Jul 13, 2009 at 5:49 AM

DOCFIXIT

✓Experienced Mechanic
18,828 POSTS

Hi
Your controls are vacuum operated and uses servos to change modes. May have faulty master select switch ie. dash controls. Do you hear a slight hiss comming from mode select switch? Need to pull out and check switch for operation and vacuum.
Let me know
Thanks for donate

Jul 13, 2009 at 6:49 AM

GUVIC

MEMBER
3 POSTS

Hi:
I looked at a manual at the auto parts store and according to it there is no vacuum lines at the dash control switch. There is only wires that run to a vacuum control solenoid under the dash. that vacuum control solenoid has a vacuum line from the engine compartment and all the vacuum lines that run to the all the door servos. I can't hear a hiss under there

Jul 13, 2009 at 7:17 AM

DOCFIXIT