2005 Suburban, never had any troubles with the A/C or heater till now. Now I have all the heat I want on the passenger side and backseat (dual controls) but absolutely no heat comes out of any of the vents on the drivers side. When we turn the A/C on it works great still. Freezing my butt off in the winter though, I need some heat when I'm driving.
Any help is greatly appreciated.

 

<!--[if gte mso 9]><xml> <w:WordDocument> <w:View>Normal</w:View> <w:Zoom>0</w:Zoom> <w:PunctuationKerning/> <w:ValidateAgainstSchemas/> <w:SaveIfXMLInvalid>false</w:SaveIfXMLInvalid> <w:IgnoreMixedContent>false</w:IgnoreMixedContent> <w:AlwaysShowPlaceholderText>false</w:AlwaysShowPlaceholderText> <w:Compatibility> <w:BreakWrappedTables/> <w:SnapToGridInCell/> <w:WrapTextWithPunct/> <w:UseAsianBreakRules/> <wontGrowAutofit/> </w:Compatibility> <w:BrowserLevel>MicrosoftInternetExplorer4</w:BrowserLevel> </w:WordDocument> </xml><![endif]--><!--[if gte mso 9]><xml> <w:LatentStyles DefLockedState="false" LatentStyleCount="156"> </w:LatentStyles> </xml><![endif]--><!--[if gte mso 10]> <style> /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:"Times New Roman"; mso-ansi-language:#0400; mso-fareast-language:#0400; mso-bidi-language:#0400;} </style> <![endif]--> I am sorry to hear of the inconvenience with your Suburban. There are several possible causes for this. It could be the heater core, the temperature actuator or the HVAC computer may just need to be calibrated. These are just suggestions, not a diagnosis.

I encourage you to take the vehicle in for an inspection by a certified technician. They will be able to offer a more accurate diagnosis with a physical inspection.

If you have additional questions, please feel free to contact me.

Louis
GM Customer Service

 

You have what I think is a Blend Door that took a poop on the drivers side, just fixed mine on my 2004 I just bought and drove it for almost 1K miles to get it home and now heat on both sides of the truck after replacing the LH blend door assembly instead of just the right side, froze my azz off the whole way home.

Went as far as stopping and stuffing plastic bags into the LH vents just to stop the cold air from coming in...Previous owner never told me about this issue and when I left Alabama it was 75 degrees outside, never thought to see if the heat worked, dropped down to 28 degrees later that night.

Good luck

 

Thats kind of what I was thinking, where is the blend door and how hard is it to fix plus how costly are the parts.

 

Found a new GM blend door on ebay, cost me $118.00, Dorman makes a replacement for around $75, I decided to go OEM and pay a little more.
Make sure you go with one with the same exact part number as the one you remove or it might not work right.

LH blend door can be accessed after pulling down the heater box cover and the LH door unit is to the right of the transmission tunnel on the heater box close to the floor. Fasteners are a little tricky to get to but doable with a little patients. Felt good to get heat back on the left side....

Good luck