Drivers side AC vents blow hot?

I feel you are correct and it is the door. The blend doors are mounted on the heater box near the heater core under the dash. this guide will show you how it fix it.

https://www.2carpros.com/articles/replace-blend-door-motor

Please run down this guide and report back.

I have dual zone automatic hvac. when driver side is supposed to blow warm air it blows cool. I have replaced the actuator behind console 4" above transmission hump just to the left of where passengers left foot would be twice and recalibrated several times several ways but still no control for driver side temperature. while recalibrating you can see the actuator turn, but afterwards when I try to change the temperature it does not move. I can open and close damper by hand when actuator is down and air temperature changes on driver side. Dealership charged me $134.00 to tell me the left temperature actuator is not working, and said they would replace it for $661.00. At my wits end as to how to resolve this problem. Please help!

The driver side air temperature control is located behind the dashboard and that is why they are charging so much because of the labor involved to pull back the dash.

Would this also cause the rear air to be cold too regardless of temperature setting?

No that would be a separate issue. Make sure both controls are switched off. The one you control up front and the rear one.

The front control will overide the rear controls.

Will it do damage to an actuator to connect the electric and power it up before it is mounted?

If you mean installing the electric connector then no. If you apply power manually yes you can damage it.

If an actuator dies on you and you get a new one but it is not in the same position, how do you get it there? I tried to install the blend door actuator and it did not line up correctly so I turned the power on to get it into the correct spot to line up. Is that called clocking it and can that do damage?

Hey RICHARD,

Just move the door pivot manually and install the actuator. Here is a guide that can help.

https://www.2carpros.com/articles/replace-blend-door-motor

Please let us know what you find so it will help others.

Best, Ken

I replaced the blend door and temp door actuators, and after at least 12 tries the recalibration worked, however if I have both sides on heat and I touch any control on the driver side the driver side temp will cool a bit and then, after a few seconds it will warm back up to the correct temp. And now the rear air will not calibrate, I was trying this because the rear air will only blow cold air no matter what temperature it is set at.

The original problem was the drivers side AC vents would all of a sudden blow hot air when AV was on. We could kill engine them restart to resolve the problem for a varied period of time...sometimes a few hours and sometimes a week.
But now our main issue is the drivers side vents do not blow any air unless you are travelling at least 55 mph them they will barely blow..... every now and then we will be driving and all of a sudden the drivers vents will work normal but that is very rare and doesn't last long. I tried pulling all fuses and letting every thing "reset" which did not work. Please advise what is needed to get drivers vents to blow again. Thanks in advance.

you are going to have to see if temp actuator for that side is getting power if it is not then it will have to be scanned for codes to see if it is control head or actuator. a local garage will have to do that. a panel must be pulled down to access it see pics.

Hey Richard,

It sounds like you have one of two problems, either you have a rear temperature sensor that is bad or the controller is shorting out.

I got rear calibrated by pulling ecc fuse for 10 seconds then replaced started car, let run 1 minute shut off for about 20 seconds and then restarted and it works! Thank you

Glad you could get it fixed please use 2CarPros.com anytime we are here to help

Best, Ken

Here is my issue: in my dual climate control SUV, the driver’s side is stuck on cold even when it is set to blow heat. The passenger and rear controls are fine. What could this be?

Good afternoon,

It sounds like the blend door motor for the heat has failed.

I attached the procedure with some pictures for you to view. The console has to be removed to access the actuator.

Roy

Temperature Valve Actuator Replacement - Left Side

Removal Procedure Notice:In order to avoid actuator damage, do not apply power to the actuator when it is not installed in the HVAC module.

1. Remove the center console, if equipped. See: Console > Removal and Replacement
2. Remove the instrument panel (I/P) insulator panel. See: Dashboard / Instrument Panel > Removal and Replacement


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3. Disconnect the electrical connector (1) from the left air temperature actuator (2).
4. Remove the screws from the left air temperature actuator (2).
5. Remove the left air temperature actuator (2) from the HVAC module assembly (3).


Installation Procedure


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1. Install the left air temperature actuator (2) to the HVAC module assembly (3).

Notice:Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.

2. Install the screws to the left air temperature actuator (2).

Tighten
- Tighten the screws to 2 Nm (18 lb in).

3. Install the electrical connector (1) to the left air temperature actuator (2).
4. Install the I/P insulator panel. See: Dashboard / Instrument Panel > Removal and Replacement
5. Install the center console if equipped See: Console > Removal and Replacement
6. Reprogram the left air temperature actuator. See: Heating and Air Conditioning > P

2005 chevy tahoe with air cond. running cold air on drivers side hot on pass. side ?

A common concern, that usually ends up being a faulty actuator. Remove the HVAC/ECAS fuse from the underhood fuse block for 10 seconds or so. Install the fuse, turn the key on without touching any controls for a minute or so. See if the function resumes to normal. There is also a reprogramming that can be done to address this concern. It is in a GM service bulletin, included below.

#06-01-38-003: Intermittent Ticking Noise from I/P, Poor A/C Performance, HVAC DTCs B0229, B0414, B0424, B3770, (Reprogram HVAC Control Module) - (Apr 27, 2006)







Subject:

Intermittent Ticking Noise from I/P, Poor A/C Performance, HVAC DTCs B0229, B0414, B0424, B3770 (Reprogram HVAC Control Module)






Models:

2004-2006 Cadillac Escalade Models






2004-2006 Chevrolet Avalanche, Silverado, Suburban, Tahoe






2004-2006 GMC Sierra Models, Yukon Models






with Air Conditioning (RPOs CJ2, CJ3)




--------------------------------------------------------------------------------

Condition

Some customers may comment on one or more of the following concerns:




•

Intermittent ticking/clicking noise from the instrument panel.





•

Recirculation mode does not work or Air Conditioning (A/C) system performance is poor during high ambient temperatures.





•

Unable to control the driver side temperature.





•

Unable to control the passenger side temperature.





•

Unable to change the front system modes.


Cause

This condition may be caused by the Heating, Ventilation and Air Conditioning (HVAC) actuators that may hunt for the correct commanded position. This cycling may cause a clicking or ticking noise.

An overtravel of the HVAC system control doors may cause one or more of the concerns listed above. If an overtravel occurs, a Diagnostic Trouble Code (DTC) will be set, and the door will go to a preset default position. When a system door defaults, that door will stay at the default position until the DTC is cleared. After the DTC is cleared, the door will operate properly until the overtravel condition re-occurs.

The following table lists the HVAC system doors and the DTC associated with it.




System Door


Overtravel DTC




Air inlet door (recirculation door)


B0229




Left temperature door


B0414




Right temperature door


B0424




Front system mode door


B3770


Correction

Technicians are to perform the normal diagnostic procedures in SI for these concerns. If diagnostics show that the HVAC system door(s) travel below 5 counts (out of the lower range) or above 250 counts (out of the upper range), then update the software calibrations in the HVAC control module. The new calibrations were made available to dealerships as part of TIS2000 incremental satellite update version 2.5, which was broadcast to dealers in February 2006.

The new calibrations have been updated to compensate for the actuator overtravel condition, the actuator hunting and the ticking/clicking noises. The new calibrations effectively eliminate the codes listed above, the default position of the doors associated with the DTCs and opens up the feedback position value. The new calibrations should not be used unless the vehicle has one or more of the customer concerns listed above or a DTC listed above has been set. The new calibrations will not correct any other DTC or A/C system performance concern.

The driver side AC will blow cold air, then for no reason it will start blowing hot air. when it blows hot air the passinger side will continue to blow cold. This happens when the controls are in auto or when it is controled by the seperate temperature selectors. I do not know if this is related but at differant times the Speedometer stops reading correctly. It happens when I am stoped, when I take off the speedometer only goes up to 30 or 40 MPH, or it might stay at zero. Everything else on the dash is working fine, tach, odometer, crusecontrol.

The speedometer issue is more than likely a fault within the cluster. There was a special coverage adjustment made to your vehicle to address cluster issues, unfortuately yours is out by miles, it only went to 7yrs/70k miles.
When your hvac system acts up, does it eventually correct itself, more so after ignition cycling? There are a couple bulletins regarding this, and I have also addressed it on a 2004 Tahoe of a friends. If it stays around for a while, perform this recalibration procedure(ignore step 3), and see if proper operation resumes, it may only be for a short time.
Important: Do not adjust any controls on the HVAC control module while the HVAC control module is self-calibrating. If interrupted, improper HVAC performance will result.

Alternate Method (w/o Scan Tool)

Place the ignition switch to the OFF position.

Remove the HVAC/ECAS fuse for a minimum of 10 seconds.
Install the HVAC/ECAS fuse.
Start the vehicle.
Wait 40 seconds for the HVAC control module to self-calibrate.
Verify that no DTCs have set as current DTCs.

If that corrects it, but it is only temporary, you more than likely have an actuator that is overtraveling. This is what I ended up having to do with the friends tahoe, and he has had no issues since(been about a year or more).
#06-01-38-003: Intermittent Ticking Noise from I/P, Poor A/C Performance, HVAC DTCs B0229, B0414, B0424, B3770, (Reprogram HVAC Control Module) - (Apr 27, 2006)


Subject: Intermittent Ticking Noise from I/P, Poor A/C Performance, HVAC DTCs B0229, B0414, B0424, B3770 (Reprogram HVAC Control Module)


Models: 2004-2006 Cadillac Escalade Models

2004-2006 Chevrolet Avalanche, Silverado, Suburban, Tahoe

2004-2006 GMC Sierra Models, Yukon Models

with Air Conditioning (RPOs CJ2, CJ3)




--------------------------------------------------------------------------------

Condition
Some customers may comment on one or more of the following concerns:

• Intermittent ticking/clicking noise from the instrument panel.

• Recirculation mode does not work or Air Conditioning (A/C) system performance is poor during high ambient temperatures.

• Unable to control the driver side temperature.

• Unable to control the passenger side temperature.

• Unable to change the front system modes.

Cause
This condition may be caused by the Heating, Ventilation and Air Conditioning (HVAC) actuators that may hunt for the correct commanded position. This cycling may cause a clicking or ticking noise.

An overtravel of the HVAC system control doors may cause one or more of the concerns listed above. If an overtravel occurs, a Diagnostic Trouble Code (DTC) will be set, and the door will go to a preset default position. When a system door defaults, that door will stay at the default position until the DTC is cleared. After the DTC is cleared, the door will operate properly until the overtravel condition re-occurs.

The following table lists the HVAC system doors and the DTC associated with it.

System Door
Overtravel DTC

Air inlet door (recirculation door)
B0229

Left temperature door
B0414

Right temperature door
B0424

Front system mode door
B3770


Correction
Technicians are to perform the normal diagnostic procedures in SI for these concerns. If diagnostics show that the HVAC system door(s) travel below 5 counts (out of the lower range) or above 250 counts (out of the upper range), then update the software calibrations in the HVAC control module. The new calibrations were made available to dealerships as part of TIS2000 incremental satellite update version 2.5, which was broadcast to dealers in February 2006.

The new calibrations have been updated to compensate for the actuator overtravel condition, the actuator hunting and the ticking/clicking noises. The new calibrations effectively eliminate the codes listed above, the default position of the doors associated with the DTCs and opens up the feedback position value. The new calibrations should not be used unless the vehicle has one or more of the customer concerns listed above or a DTC listed above has been set. The new calibrations will not correct any other DTC or A/C system performance concern.

Your programming of the HVAC control module will more than likely have to be carried out from a dealer terminal, this type of stuff is somewhat proprietary to GM.

The temperatures for both sides are set to hot. However, the driver side is blowing cold. Is the blend door I need to replace under the quiet panel (really easy to replace) or buried in the dash (really hard to replace?

Thanks,
Jon

Hello, I'm Danny.

Yes, it sounds like you are having an issue with the blend-mode door actuator. It is a small electric motor that opens and closes a door flap to route airflow through specific ducts in the hvac box to specific vents depending on setting. Here is a tutorial showing how to replace a blend-mode actuator:

https://www.2carpros.com/articles/replace-blend-door-motor

I've attached picture steps below showing removal and replacement of the actuator for your vehicle. Hope this helps and thanks for using 2CarPros.

Thank you for the quick response. I have found and removed the actuator that is easy to get to. However, when I turn the actuator by hand it only heats the right side. I see the diagrams you sent but truthfully they don't make much sense as I am not a mechanic. Where is the actuator that controls the heat for the left side? Thanks, Jon

DANNY L is one of our best! If you click on the guide it explains where the actuators are and what they do.

https://www.2carpros.com/articles/replace-blend-door-motor

Please run down this guide and report back.

I replaced the main head control of the HVAC system because my fan only had 2 speeds. High and off, when the fan was set to off it was on high, and vice versa. Replaced the head and the fan speeds are working correctly. But now, the only warm air comes from the middle and passenger vents. The drivers side is cold air. I replaced the actuator under the driver side dash and the issue remains.

Good morning,

I would remove the heater hoses from the firewall and flush the heater core. Use a garden hose to flush the dirt and debris. Run it both ways until you get a good even flow.

https://www.2carpros.com/articles/car-heater-not-working

Beyond that, you may need a heater core.

https://www.2carpros.com/articles/replace-heater-core

Roy

Heater Core Replacement

Removal Procedure

1. Drain the coolant. Refer to Cooling System Draining and Filling .
2. Remove the instrument panel storage compartment. Refer to Instrument Panel Carrier Replacement .
3. Disconnect the electrical connectors, as necessary.
4. Remove the center floor air distribution duct.
5. Remove the hinge pillar trim panels. Refer to Instrument Panel Carrier Replacement .
6. Remove the blower motor cover.
7. Remove the blower motor. Refer to Blower Motor and Fan Replacement See: Blower Motor > Procedures.
8. Remove the steering column. Refer to the applicable procedure:
- Steering Wheel Replacement in Steering Wheel and Column - Standard: See: Steering Wheel > Procedures
- Steering Column Replacement in Steering Wheel and Column - Tilt: See: Steering Column > Removal and Replacement
9. Roll back the instrument panel. Refer to Instrument Panel Carrier Replacement .
10. Remove the coolant recovery reservoir. Refer to Coolant Recovery Reservoir Replacement See: Coolant Reservoir > Procedures > Coolant Recovery Reservoir ReplacementSee: Heater Hose > Procedures > Heater Hoses Replacement.
11. Remove the heater hoses. Refer to Heater Hoses Replacement .


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12. While holding the heater case to the cowl, remove the screw on the interior side of the cowl, near the evaporator pipe, if equipped.


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13. On the engine side of the cowl, remove the 4 screws that hold the heater case to the cowl.
14. On the engine side of the cowl, remove the 2 nuts that hold the heater case to the cowl.
15. Remove the heater case.

Ask an assistant for help, if necessary.

16. Remove the 7 screws that hold the heater cover to the heater case.
17. Remove the heater cover.
18. Remove the heater core from the retainer.

Installation Procedure

1. Install the heater core into the retainer.
2. Install the 7 screws that hold the heater cover to the heater case. Replace the seals.
3. Install the heater cover.

Verify that the heater cover is properly sealed.

4. Install the heater case.

If necessary, ask an assistant for help.