My heater blows out cold air on the drivers side and works fine on the passengers side. Do you know what is causing this?

SOURCE: 04 Chevy Avalanche Driver's heater blowing cold all the time

your mode actuator is stuck. try unhooking battery for a few minutes when you hook back up actuators will do a relearn.if this does not work will need to have replaced

SOURCE: heat works on driver side, passenger side blows cold air.

Did you check your coolant level or was it low and you added to it at some point? If so the system my need to be bleed or worst case the thermostat is going bad.

Jeffery Lewis

• 329 Answers
• Posted on Jun 03, 2009

SOURCE: 2004 Chevy Silverado AC is blowing warm air on passenger side.

You have dual zones that are controlled by temperature actuators the passenger side has lost its memory or has gone bad you can put it in self programming by disconnecting the battery for ten minutes then hook it back up start the truck turn the temperature control on but do not touch any other controls let it go thru the self programming for about 6 to 7 minutes then select your temperature you want if it still does not work properly you may have a bad actuator or a bad connection at the actuator

SOURCE: Blowing cold air ,no heat

Not exactly certain, but sounds like you have a broken "blend door" or acuator malfunction

SOURCE: no heat of drivers side blows cold air while

Replace the door blend actuator behind glove box, approx $150 for part, Everyone I know with dual control on the silverado's have this problem.