Heater only works on passenger side.

Does the vehicle have dual zone climate control, where the driver side and passenger side have different control? Sounds like a blend door issue on the driver side. Why did you replace the passenger side, was it blowing hot too when AC was on?

If you're comfy with manuals then i know few websites that can help you with it. Bcause I've got it from various websites so I
know how each site deals. try www.reliable-store com . Very helpful

Slide control obviously not working.

2004 Chevy Tahoe. Hot air out of vents on driver's side, cool ...

answers.edmunds.com > Edmunds Answers

Jun 25, 2009 - Hot air from vents-driver side and cool air from vents on passenger side. ... The driver's side vents were blowing out hot air, and everything else wasblowing cold. ... you'll literally have to restart your tahoe/yukon at every traffic light to keep cold air coming ... I was also getting air only out of the defrost vents.

Hot air out front drivers side vents 05 escalade - YouTube

? 3:14
https://www.youtube.com/watch?v=5lnd8UNcx6M
Aug 3, 2013 - Uploaded by South FL Mud Club
Suddenly hot air started blowing out the air vents only on the drivers... ... is a very helpful video ,I wondering if this part number apply for my 04 chevy tahoe? .... I have cold air out of thepassenger side, but warmer air out of the driver's side. .... 2003 Tahoe No Rear Heat Fix, Suburban, Yukon XL Repair!

Heating and AC Temperature and Air Delivery Mode Door ...

repairpal.com > Problems > Chevrolet > Tahoe

Driver/passenger air vents blow hot then cold when using A/C. Back to cold when you restart the vehicle. Upvote (35) ... 2003 Chevrolet Tahoe ... I have a 02 Tahoe ,and the heat system is working only on the ceiling side of the car when turn.

2004 Chevrolet Tahoe Blows Hot Air - Sparky's Answers

Just had this happen today to my 2007 silverado heat on the right side cold air on the left side. After engine was off 15 minutes and restarted heat was on both sides. I'm guessing a relay failed to open door to allow the heat to flow thus blowing cold air.will monitor diligently for a while.

Well had the same issue on my duel climate controll 04 2500HD but changing the heater control solved the different temp.The only other thing would be your mixer door motor.There are two,one for DR side is probibly stuck..As far as the blower motor.The resister should have taken care of that.Sounds like you may have another bad one.May want to take a volt meter to the resister plug in and run you different fan speed just to make sure that you get voltage to the different conecters.

Check movement of vent doors on that side. Sounds like they aren't moving over as they should. (Or hose fell off on passenger side.)

something fell down defrost vent

Check blend door actuator for operation

You will need to replace your driver side temp actuator. It is most likely sticking or over travelling. It is located under the dash directly below the a/c control head. It is bolted to the a/c box upside down with two small bolts. Let me know if i can help more.