04 LS, DCCV or Blend door??? Or maybe something else?

samuelsteven

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Ok, so I purchased an 04 LS Ultimate from a relative a little while back, it had been in a front/left collision and was repaired for the most part. There are a few different problems that I need to troubleshoot.

First off, the a/C and heater aren't working correctly. I was told that my wife's cousin which was the previous owner had her mechanic check it out because it was only blowing hot air all of the sudden. She was told that it was the Dual Climate Control Valve. She didn't want to replace it because the part was costly at the time, so the mechanic some how bypassed it for temporary and she said it fixed the problem for now. Well, when I first drove it, the air was blowing ice cold, but once I got up to higher speeds, it would turn to heat. Im not sure how he bypassed it, Im guessing its like bypassing a heater core? Anyhow, I was gonna go ahead and by a new DCCV tomorrow, but this is what makes me think twice about it. Often, I get a knock that comes from behind the dash in the steering wheel area, its like something is moving too far and hitting the under side of the dash.
I'm thinking maybe a blend door actuator moving too far? If there is a blend door under there? And if so, could that be the problem and not the DCCV? Im wondering, if its supposedly bypassed, should it still blow hot and cold air?

Another problem is that the drivers side front wheel isn't centered in the wheel well, it sits more toward the firewall and has a big gap from the bumper. Im guessing they didn't fix that part, maybe a bent lower control arm? The car does drive straight, Im guessing instead of fixing it, they just aligned it.

The ride of the car is pretty rough but not really bad, Im hoping a full alignment will fix it, since I do notice some tires wearing more then others. The car doesn't have air suspension does it?
 
Okay, for the one-hundredth time - the LS does not have a air temperature blend door.

It's the DCCV. Plus, you will have to find and undo whatever was done to bypass it.

There are electric air doors that control where the air goes. Maybe you are hearing one of those, however it's more likely you are hearing one of the motors that position the steering wheel. Normally, you can't hear the air doors when the car is running. You can hear them faintly for several minutes after the car is turned off.

The suspension parts on the LS are aluminum. Any that are the slightest bit bent must be replaced. Steel bends and can be bent back. Aluminum cracks.

No air suspension.
 
Just replaced DCCV

Ok, just replaced the DCCV and nothing has changed! Still no heat, I'm not sure but it seems like theres little if any coolant getting through the top radiator hose, which also feeds the DCCV from the "T". I mean I feel the radiator hose and its hot, but if I squeeze it, its like there not much pressure, it collapses easily. I would think that hose would be pretty stiff when the coolant is circulating. Im wondering if this was the cause in the first place.

Any insight?
 
Check the underhood fuses. I needed the DCCV replaced on mine and when it went it blew a fuse under the hood. Once that was replaced the heat/air works fine.
 
Ok, fuse was good. No i didnt bleed the air out of the cooling system, didn't know I needed too. I left the cap off of the coolant reservoir because I figured there was air in it, because the reservoir was making this real ugly thudding sound, almost like a sound you hear when ur car is overheating. It lasted for about 10 minutes and stopped. How do I bleed it?
 
Ok, fuse was good. No i didnt bleed the air out of the cooling system, didn't know I needed too. I left the cap off of the coolant reservoir because I figured there was air in it, because the reservoir was making this real ugly thudding sound, almost like a sound you hear when ur car is overheating. It lasted for about 10 minutes and stopped. How do I bleed it?

You need to follow this procedure exactly.

http://deneau.info/ls/s6x~us~en~file=s6x33004.htm~gen~ref.htm#extract_142
 
Did you pull all the hoses off?

They get clogged up......from the 'T' back to the DCCV back towards the heater core.

It is a simple 30 minute job,(or less), to remove all hoses on a Gen2 and clean them.

my hoses were completley gunked up..................BAD
 
I will have to try and clean them tomorrow. I just don't see that being the problem, the coolant that I saw come out, looked pretty good. It doesnt even try to get a little bit warm.

One thing that I was confused about is which sides the hoses that goto the heater core went on. Since she previous owner said it had been bypassed, I thought maybe they switched them, but I dont see how that would bypass the DCCV. Im not even sure that it matters, arent they just to control the passenger and driver sides seperately? I guess if they're wrong the only thing that would happen is the driver heat/ac controls would operate the passenger and vise versa?

Can anyone tell me which hose goes where?
 
if I remember correctly.....

the right side of the DCCV goes back to the lower tube/hose going to the right side of the heater core

the left side goes to the top left to the core
 
Ok, I found it on my AllData program. The top hose coming from the heater core goes to the right port on the DCCV and the bottom hose goes to the left port, that being with the 3rd port to the bottom.


DCCVDiagram.jpg
 
I didn't see anything about the DCCV on that link.

I'm having internet problems...:mad:

the DCCV is a simple fix, there is one hose going in( the lower ) and 2 going out.
the 2 hoses on top, going back to the heater core have quick connects, THEY ARE THE ONES THAT GET CLOGGED OR PLUGGED, as you put it.

goto http://deneau.info/ls/ and look around....... for reasons unknown, I cant post the specific site for the DCCV, could be my stupid As s connection

EDIT: you found it!!
 
Those hoses that go from the DCCV back to the heater core are a b*tch to get off, the quick connects are in a bad spot. I tried with my fingers and a screw driver, couldnt get either one off, just unclamped them at the DCCV.
 
the quick connects are a bitch, need some long needle nose pliers, but the way they bend, (the hoses), you need to get'em off and clean them out
 
Ok, I just removed the DCCV and the hoses. I made sure each hose was cleaned and applied pressure to all hoses after I put them back and it seems like everything is flowing fine, I reinstalled the DCCV and also checked it with an ohm meter as well as the electrical connector for it. Everything checked out fine. Still, no heat but the A/C seemed to be working this morning,
i hadn't attemped to use it in a while, so I don't know if it had been working previously. I hadn't driven the car on the highway to see if the A/C will still turn off at higher speeds.

My next try will be a coolant drain and replacement. If say there was not much coolant and more water in the system, could that cause the heater not to work as well? The coolant I saw today when removing the hoses was more clear then anything, I think its supposed to be more yellowish, but I guess its hard to tell when your supposed to mix 50% water.

If that doesnt work, I dont know what else to try.
 
I just ran a self diagnostic on the DATC and it came back with 1264 - Floor door actuator circuit failure. Could this be a culprit? Im thinking its what I hear knocking on the underside of the dash sometimes
 
I just ran a self diagnostic on the DATC and it came back with 1264 - Floor door actuator circuit failure. Could this be a culprit? Im thinking its what I hear knocking on the underside of the dash sometimes

No, it's not related to air temperature output, only air direction output. It seems to be common for the LS to trip codes like this now and then even though the air doors are working correctly.
 
Great now im gonna have to do this. Might as well do it tomorrow when i reinstall my headlights. How much does it cost to replace the DCCV?
 

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