Heating not the same temp on driver and passenger sides
#1
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Hello,
I searched a bit for this problem and have not found anything. Forgive me if it exist. The Heating is not the same temp on driver and passenger sides. It seems that my driver side is about 5-10 degrees cooler then the passenger side. When I turn both to 85 F they seem about the same but around 80F, you can definitely tell a difference. Anyone else have this problem?
I searched a bit for this problem and have not found anything. Forgive me if it exist. The Heating is not the same temp on driver and passenger sides. It seems that my driver side is about 5-10 degrees cooler then the passenger side. When I turn both to 85 F they seem about the same but around 80F, you can definitely tell a difference. Anyone else have this problem?
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#3
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I also have the exact same problem. around 80 degrees the driver side is noticeably cooler than the passenger. It's weird, it doesn't happen all the time. I cant pinpoint exactly when it happens.
#5
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I suspect the difference is due to heat loss in the longer duct to the driver side.
Salim
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#8
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YES,
There is only one heater core in the dash to service both sides of the car, but the difference iin dual climate controls is that the doors in the assembly work independently of each other. They close off the heater core from the A/C when in cool (65), and the A/C core from the heater when in hot (85). Then it partially opens and closes each door simultaneously to MIX heat with coolness when in a temperature mode between each extreme.
This "mixer" assembly responds from signals from the electronic controls on the dash, which energizes motors which operates the doors.
It is possible that the display is sending the wrong signal, or the mixer is responding incorrectly.
If the coolant has been changed lately, the level could be low. I would cycle the electronic control from 85 to 65 and back slowly and listen for the doors opening and closing. Do it a few times back to back and maybe it will start working. The engine has to be running to circulate the coolant and to provide vacuum for the doors to operate.
A vacuum line could be loose, or cracked in the panel causing the mixer doors to operate erratically.
The last resort is always the dealer, but that is a horrible thought.
There is only one heater core in the dash to service both sides of the car, but the difference iin dual climate controls is that the doors in the assembly work independently of each other. They close off the heater core from the A/C when in cool (65), and the A/C core from the heater when in hot (85). Then it partially opens and closes each door simultaneously to MIX heat with coolness when in a temperature mode between each extreme.
This "mixer" assembly responds from signals from the electronic controls on the dash, which energizes motors which operates the doors.
It is possible that the display is sending the wrong signal, or the mixer is responding incorrectly.
If the coolant has been changed lately, the level could be low. I would cycle the electronic control from 85 to 65 and back slowly and listen for the doors opening and closing. Do it a few times back to back and maybe it will start working. The engine has to be running to circulate the coolant and to provide vacuum for the doors to operate.
A vacuum line could be loose, or cracked in the panel causing the mixer doors to operate erratically.
The last resort is always the dealer, but that is a horrible thought.
Last edited by gserep1; 12-28-06 at 01:06 PM.
#9
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I have this same problem. It gives me the chills anytime that it happens because usually the vents are just pointed on me. If it's cold out I usually have the drivers side vent closed to keep the cold air from coming out and leave the passenger sides open to get the warm air to come out. It sucks.
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#13
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Wow I thought it was just mine, okay so this seems like this a pervasive problem with these cars and it's time for a fix. From what I can tell there are two servo motors that service the HVAC system for GS3/4. Any of the experts can jump in here cause I'm thinking out loud and going from my very limited experience at the same time. The first problem I was having was due to a bad air/mix servo. That is the control that shifts air flow from defrost, to feet to face or the mix of face and feet. You can access the system through the glove box behind the cd changer and in-car air filter. I'll attatch the proper pdf's in a later post. Anyway, I diagnosed that servo was bad after I took it apart and the tines inside were fubar. $130.00 later(dealer only part) I fixed that problem and thought I was home free, but now I figure out that the passenger side only blows cold air no matter what temp the control on that side is set at. My limited knowledge of HVAC would lead me to believe that air is not passing over whatever it needs to pass over to provide heat, weather it's coils, water, whatever. Could this be the other servo motors job or are we looking at something else entirely. Someone must be able to point us in the right direction? It's crazy that we all drive around with half a car chilly cold and the other half nice and warm...makes for a cranky passenger or driver....
#15
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If I was a betting man, I'm guessing this is the one if your passenger side is cold...once again anyone with the proper knowledge who can confirm or steer us in the proper direction would be greatly appreciated....D