Air Conditioning Troubleshooting A/C Blows hot on one side 2002 2003 2004 2005 Thunderbird


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As I stated a few times my a/c has been giving me trouble for about 3 years now. I have had the system dye tested twice and recharged twice only to have no a/c again about 6 months later. I went so far as to change my DCCV to no avail. Boy was that fun!
this past Monday I decided to bring her to Beach Ford in Myrtle Beach. She is still there and still no answers. I told them to keep the car until they have a definitive answer. The dye test showed a minuscule leak at the compressor but even they say it’s not the underlying cause. They are going to keep her now until next week trying to determine if the issue is under the dash where the dye can’t be detected. My cousin was a master mechanic with Ford and Nissan and says this should not be that big of an issue....
I’ll keep you guys posted....
I was fighting off and on air conditioning problems for a couple of years replacing various parts and recharging. I finally accidentally found one of the plugs behind the A/C heater control panel had worked its way partially loose. I plugged it in properly and it has been fine now for two years.


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Well as I stated I would update you all on my a/c issues. The dealer in Myrtle Beach had my car for a week and could NOT find any issues with my unit. They recharged the system and I picked up the car yesterday blowing frigid air. The service dept suggested I drive it for a week or so and then bring it back to them to check pressures and see if any dye is present anywhere. They said they drove car for 70 miles and ran the a/c through her paces and nothing. I think they we’re just joyriding.... I’ll never know.
Anyway that is where we stand

Ok, I'm starting to put a few pieces together. Lately my car's been doing the "heat when you floor it" thing more often and it lasts longer each time too. One thing I noticed that my car would do for the past couple of months is when I key off, I hear what sounds like a vacuum actuator groaning inside the dash somewhere behind the stereo. I suspect what's actually going on is that the diaphragm in the heater blend door actuator is either gummed up, or leaking and unable to maintain pressure, and when you goose the throttle, the vacuum pressure drops, the flap moves a bit, and allows the air passing through the heater core to basically negate the condenser air. The more you throttle it out, the more the flap opens for heat, the hotter the air, the longer it takes to "reset" itself (for instance when some of you guys suggested shutting down and trying again after a few minutes (vacuum pressure backs off, flap moves on its own).

Granted, this is all theory until I get it apart, but it sure sounds like that's what's misbehaving in there. Even the groaning noise started changing the longer this has been going on for me. The good news is .. the valve is cheap 30-60 bucks. Here's the kicker though - the valves appear to be electric, not vacuum - but sure as heck behaves like a vacuum one.

There's several numbers from Dorman, but what I'll probably try to do is get the old one out, or at least where I can see the Ford p/n then cross it before buying a new one. Anyway - I noticed the part numbers at the top of the thread made no mention of this before - just throwing it out there.

Dorman numbers at a quick glance show a ton of these darn things :

604-919 - for defroster (you may see condensate on the lower center of your windshield if this one is starting to fail and not close off the center defroster vent)
604-914 - for main temperature (my suspected culprit)
604-912 - air distribution to floor (guessing you'll feel air bleed off near your feet)
604-264 - main distribution panel (not sure about this one)
604-266 - main distribution air inlet (assume this is between fresh and recirculated air)

There were other numbers but those were the same models with 1 year warranties, the above ones are "limited lifetime" ones. Anyway, I'll probably start tracking down the source of the groaning and go from there.
I have had that noise for years, even after I turn ignition off it still sounds exactly like you described. I don’t think that that would be the cause of Freon loss unless I’m missing something...
I've been dealing with my wife's 2004 (32k miles) T-Bird AC problems for about a year. I've replaced the DCCV, which seemed to work for about a month. I tested the CCM which seemed to be fine. When it blew cold air it was very cold so I figured the freon charge was fine. Finally I just clamped off the hoses going to the firewall from the DCCV and life was good (we live in Florida).

It started blowing hot again last week so I went to the nearest auto parts place and bought more freon with a leak sealer. The T-Bird sucked up the whole can and some I had on the shelf. The following day the compressor stopped working. I gave up so I took it to a repair shop today. The technician said he had to evacuate the freon because of the sealer, apparently it does something to their equipment and I over-charged it by .75 pounds (I thought it only took what it could handle). He said the bad news is that the "Left Temp Blend Door Motor' also called the "Left Cold Air Bypass Motor" was bad but they are no longer available because of Covid.

When I went to pick up the car ($72.90) the owner gave me the OEM part number XW4Z U19E616-EA (HVAC Floor mode door actuator). After a quick Google search I found several but none that referenced left or right. I also found XW4Z U19E616-DA with that search request

I'm hoping that one of our club members might have some insight.



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He said the bad news is that the "Left Temp Blend Door Motor' also called the "Left Cold Air Bypass Motor" was bad but they are no longer available because of Covid.
What a clown. Not available because of Covid? How about, not available because the car is almost 20 years old, they only sold a limit number so there are not a lot of aftermarket parts. Or better yet, not available because the part does not exist. LOL This statement alone would be enough for me to get someone else involved for another opinion. What is the part number he's referring to? The answer to that should be interesting!

The only part I'm familar with is the YFRH-19E616 Blend Air Door Actuator. You can buy those on ebay-
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Finally I just clamped off the hoses going to the firewall from the DCCV and life was good (we live in Florida).
Hello Everyone!

First time poster on the forums, though a long time lurker. I have had on and off troubles with my Climate Control since purchasing the car. Started out originally blowing hot air on both sides, we changed the Dual Heater Control Valve, which fixed my issue for a little while. Then after about a year of driving it started pumping out hot air again, but would flip back to cool after turning it off. A few months pass by, and my Climate Control does a complete flip. Blowing out freezing cold air. Which, being the summer months, I was okay with. However, I am moving down to Florida and wanted to correct any issues before I move down. So I took a look at my Heater Control Valve again, and found it was completely blocked up. Replaced it again, and upon replacement has been blowing hot air on the driver's side, and cooler (but not correct) air on the passenger. So I took it to my local Ford service center, they said the Control Valve was defective, replaced it, but to no avail, same exact issue as before. I am at a loss. As I am moving down to Florida tomorrow, we are working up a quick fix for this so I am not scorching in the Florida sun. I am going to assume my problem has something to do with electrical components so any help in that direction would be great. But for now, my only option is to clamp the hoses. I tried it today, but couldn't figure out a proper way of doing it. I would love any advice, on what clamps you use to clamp it off, where on the hoses you clamped them etc. It seems to be my only option, as my moving is imminent!

Thank you so much!!!

You have the same DCCV as I do. Mine went bad back in May and I could not get one fast. So I removed the two 5/8" heater hoses from the DCCV and used a 5/8" hose connector to join them together. Then used rubber 5/8" caps that I got at Auto zone (they came in an assortment package) and put them on the plastic pipes on the DCCV. all with hose clamps.
I received the new valve but it's too hot here in Las Vegas to work on a car. I will put the new DCCV on in Oct.

I bought the new valve on Amazon.
Part# XR840091 Heater Control Valve For 2003-2005 Ford Thunderbird 2002-2008 Jaguar S-Type 2003-2006 Lincoln LS - Replace Part Number 2R8Z18495AA
Sold by: Surwit Auto Parts
Return window closed on Jun 29, 2021


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This part can be confusing when ordering because the model years listed for Lincoln LS and Thunderbird vary and sometimes confusing. The 2002 Thunderbird using the on with 5 ports and the 2003-2005 uses the one with 3 ports. That's how you know which one to order.

2002 Five Valve DCCV Replacement part
Purchase on Amazon here -
Purchase on eBay Here-

2003-2004-2005 Three Valve DCCV Replacement part
Purchase on Amazon here-
Purchase on eBay here-