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Eighth generation of the Mazda Protege.

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Heater only blowing out front vents, no heat to feet or defrost. Why?

Heater working but only blows out front vents. No heat to feet or defrost. Before replacing Heater Control Unit, it would only blow hot air from front vents- With this replacement it will now change from cold to hot and the air flow pressure does change from the front vents when changing the setting dial but there is still no air at all to feet and defrost. Can anyone tell me if there is a louver or valve that could be jammed and where to locate it? Or what else to try? Thanks!

Desperately Seeking Defrost :)

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Thanks for information. Looking for repair guide but would appreciate any info on where to find actuator or regulator. Cheers!

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I have this problem too but with 2007 Chrysler Aspen. Had the blend door replaced and still no heat on the floor. As a matter of fact when you turn the knob to the floor vent it’s coming out of the top defrost panel b

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I have a problem my 1999 Chevy Tahoe I cant get no heat or air to blow on feet all other vents work good except for the floor vent

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2015 nissan rigue heat air only comes out of vents won't change to feet or defrost what do i replace to fix it

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@nothotwheels , Most likely a AC/ Heat, blend door actuator problem. Actuator could be stuck, faulty, linkage off, etc. Could not find a link for the 1998-2003 protege but will post a link to show and tell in general where and what to look for. You may also find a reasonably priced repair manual online or at the local library to borrow. Good luck.

I hope this helped you out, if so let me know by pressing the helpful button.

https://www.2carpros.com/articles/replac...

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@lpfaff1 I know you like to ask for up votes but take a look at how that is working out for you and where your votes are actually coming from.

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@mayer , I have noticed and appreciate and I also return as you suggest, what is also nice when poster's do post back accepting the answer and leaving a comment of their gratitude, it makes it feel worth while. I am still learning things about this site and with guidance from you and others things should be good. Mayer , have also noticed you have not been answering as much as you were before, busy at the office I suppose. If I am missing something here let me know! Have a good evening.

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unplug battery for 30sec. it will reset

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it must be the cable thats hooked up in to that regulator that changes the direction of air

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How do I located the heater control

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The actuator typically on any vehicle has a flap that is controlled either manually by cable or by vacuum operated cable. It can be a labor intensive job to get to the heater box flap and then find a vacuum leak. See if you can get a shop manual on your make of car.

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From a picture of your control panel (googling your model and "heater control unit" and looking at a picture of the back it appears you have a rotating switch that applies a vacuum to a set of tubes connected to a single connector. It's possible this connection was not made at the vehicle side, or that the vacuum line is clogged.

Usually, if left off, the engine vacuum will not cause the engine to idle rough or to set an OBD code. You could try removing the end of the connector if it's on, and see if the engine idles differently. The new unit could be faulty, as that's the only thing using engine vacuum on that unit, it appears to me...

Also, maintenance on the vehicle or just age could cause the flaps or actuators to bind or jam but it's usually not a coincidence when work is done and something else stops working... Anyway, nobody likes to work under the dash and prices reflect that. There's a lot of brittle, sharp items under there.

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N Wiegand will be eternally grateful.
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