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front HVAC vents not blowing, actuator location ?

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Old Sep 7, 2025 | 01:48 AM
  #1  
OVERLANDH2's Avatar
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Default front HVAC vents not blowing, actuator location ?

Hey guys on my 2004 H2 front vents are not working and also the rear vents are not working,
I believe it’s the blend door actuator?

where is this actuator located?

thank You.
 
Old Sep 7, 2025 | 06:12 AM
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From the wiring diagram, there are 4 actuators:-
  1. LEFT AIR TEMPERATURE ACTUATOR (LOWER MIDDLE UNDERSIDE OF HVAC ASSEMBLY)
  2. RIGHT AIR TEMPERATURE ACTUATOR (MIDDLE TOP OF HVAC ASSEMBLY)
  3. MODE ACTUATOR (LEFT SIDE OF HVAC ASSEMBLY)
  4. RECIRCULATION ACTUATOR (TOP FRONT OF HVAC ASSEMBLY)
Not an expert on these, however from the various posts it seems the above parts are not all the same and replacing them is not easy. The rear air vents are possibly piped to the front ducts with no separate actuator, but I'm not 100% sure about this

The question is are all the actuators not working?

Its' unlikely they've all failed so it could be a wiring issue or HVAC issue

It would be worth spending some time researching and possibly using a Tech2 diagnostic tool before undertaking any serious work, actuator issues will normally have a DTC associated with them which will help finding the root cause.

It may also be worth performing a recalibration, there's a procedure using a Tech2 and also this alternative (probably steps 5 to 9) :-

Alternate Method (w/o Scan Tool)
  1. Clear all DTCs.
  2. Place the ignition switch to the OFF position.
  3. Install the HVAC actuator.
  4. Connect all previously disconnected components.
  5. Remove the HVAC/ECAS fuse for a minimum of 10 seconds.
  6. Install the HVAC/ECAS fuse.
  7. Start the vehicle.
  8. Wait 40 seconds for the HVAC control module to self-calibrate.
  9. Verify that no DTCs have set as current DTCs.


 
Old Sep 7, 2025 | 09:59 AM
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Thank you

it’s only blowing from the top under the windshield.
 
Old Sep 7, 2025 | 10:04 AM
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Is there any particular TECH2 scanner you guys recommend? I would like to buy that.
 
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