Q: AC blows hot and cold air at the same time

asked by on

I live in a very warm area, so I notice right away whenever something is up with my AC. Half of the vents in my 2007 GMC Acadia were blowing warm air the other day. I find it pretty weird that only part of the AC broke. The truck has just under 70k miles on it and I haven’t really had major problems so far. What part should be inspected first?

If you are getting normal cold air out of driver’s side and warm air out of center and passenger vents then you most likely have a bad temperature blend door actuator for the passenger side on the A/C evaporator case. Your system has two of these actuators, one for each side of your dash vents. This controls the temperature by getting feedback from the inside ambient temperature sensor. The sensor looks at the drivers and passenger seat temperatures and can alter the left and right side of your dash temperature output to compensate. You could have YourMechanic scan and test your A/C system for problems. Once a thorough diagnostic report is produced and indeed the actuator is deemed to be the culprit, YourMechanic can provide you with the best estimate for repairing the failed part.

Was this answer helpful?
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details
  1. Home
  2. Questions
  3. AC blows hot and cold air at the same time

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Q: Hi, Have a 2002 Vauxhall Corsa. Installed a brand new crank angle sensor and now oil is leak from the area. Would you know why?

You may have damaged the mounting O-ring seal on the sensor was torn when installing. Remove the sensor and then check the seal O-ring to see if it got damaged and replace as needed. Make sure to lube the seal...

Q: My car is jerking and has reduced engine power

Hello and thank you for contacting YourMechanic. Your vehicle may have a clogged catalytic converter or muffler. This message displays if the back pressure on the engine is too high. Start the engine and get something to block the...

Q: I accidentally put washer fluid into the coolant Reservoir. what harm can this cause? it was about 3/4 of the bottle.

Hello, yes this can break down the coolant and it can become acidic. The coolant system will need to be flushed. If you'd like, a certified Your Mechanic Technician can come to your location to perform this. Please look at...

Related articles

How Long Does a Heater Control Valve Last?
Keeping the right amount of coolant in a car is essential in keeping the engine at the right temperature. Failing to have the right amount of coolant or even bad elements...
P0240 OBD-II Trouble Code: Turbocharger Boost Sensor B Circuit Range/Performance
P0240 code definition Turbocharger Boost Sensor B Circuit Range/Performance What the P0240 code means P0240 is an OBD-II generic code triggered when the Engine Control Module (ECM) detects the intake boost...
P2103 OBD-II Trouble Code: Throttle Actuator Control Motor Circuit High
P2103 means there is a fault with the throttle actuator control motor circuit, likely due to a defective electrical component or part.