Need Help?

2004 GMC Sonoma SLS Crew Cab 123 WB 4WD

2004 GMC Sonoma
Trim Info:
4-Wheel Drive, Crew Cab 4.7' Fleetside SLS
15 mpg city / 19 mpg hwy
Other Trims
Do you own this car?
Estimated Mileage
Enter current mileage for most
accurate info about this vehicle

Track Your Service Records
Get Recall Alerts
Get Updated Value Estimates on Your Car.
back to question list

Ask the Community

Ask Our Auto Mechanics

August 26, 2012, 1:47 pm

Travis K

Question: Where is the blend door located?

When i turn the blower on in my 2002 GMC sonomo, the first and second speeds do not work, the third and fourth do, but nothing comes out of the vents, floor, or defrost, and it makes a whistle noise. My thoughts are that the air is blowing through, but is being cut off and the air is what the whistle is(like blowing into a bottle from the side). I would like to start checking what it could be, rather than be charged by the hour just to look around. I thought Id start with the blend door, but i cant find its location.

September 9, 2012, 9:02 pm

Elizabeth K

Here is some info on the blend door:

If the 1st and 2nd speeds of the blower motor don't work, you may want to check the blower motor resistor.

0/0 users found this helpful.

Ask our panel of certified auto mechanics a question. We pay for their advice so you don't have to

My Auto Score

See the free AutoCheck score

Meet The Experts
Kim Perrin
Kim Perrin is our resident mechanic here at DriverSide. Kim worked as…
Tyler Orr
Tyler Orr is an expert in German and Japanese cars and has been a mechanic …
Elizabeth Kriesten
Elizabeth Kriesten worked as an automotive technician for several years at Dodge…
Tips on Servicing

Car Brakes: How Do You Know When to Change Them?

By Zach Bowman For those who suffer a daily commute through heavy traffic, your vehicle's braking system can bring thousands of pounds of metal, plastic and empty Starbucks cups to a stop hundreds of times before you get to work. It goes without saying that these pieces wear out, but they do so slowly, meaning you may not notice they need attention until ...

Read more…