Climate Control Mixer
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98 C43
Climate Control Mixer
I noticed that when I increase the temperature from cold to hot, it either takes a very long time for the temp to switch, or it doesn't do it at all. The climate control unit appears to be working fine, visually. Is this an issue with a mixer?
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98 C43
Anyone? More specifically, the car will go to HOT and COLD, but doesn't seem to like anything in between. AC works fine too. I cleaned out the Duovalve to no avail. Any help would be greatly appreciated.
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From: Chapel Hill, NC/Montreal, QC
1995 C36 AMG, 1998 C43 AMG
Did you check/replace the interior thermometer? I've noticed that with mine too. I always just assumed it was the way the climate control worked vs. normal AC. If I lower the temp a bit it will do so gradually, and if I want cold air to start blasting I have to drop the temp by like 10 degrees
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98 C43
Did you check/replace the interior thermometer? I've noticed that with mine too. I always just assumed it was the way the climate control worked vs. normal AC. If I lower the temp a bit it will do so gradually, and if I want cold air to start blasting I have to drop the temp by like 10 degrees
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From: Chapel Hill, NC/Montreal, QC
1995 C36 AMG, 1998 C43 AMG
I imagine an error would come up if it was really fried, but after 16 years it can get full of dust and stuff. They're pretty cheap from what I remember, so I just replaced mine when I got it.
It's located under the black plastic bit where the dome lamps and sunroof button are. If you pull down that whole thing it's a little black cube in the top. You can locate it from the vents on the bottom side of the plastic
It's located under the black plastic bit where the dome lamps and sunroof button are. If you pull down that whole thing it's a little black cube in the top. You can locate it from the vents on the bottom side of the plastic
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98 C43
I imagine an error would come up if it was really fried, but after 16 years it can get full of dust and stuff. They're pretty cheap from what I remember, so I just replaced mine when I got it.
It's located under the black plastic bit where the dome lamps and sunroof button are. If you pull down that whole thing it's a little black cube in the top. You can locate it from the vents on the bottom side of the plastic
It's located under the black plastic bit where the dome lamps and sunroof button are. If you pull down that whole thing it's a little black cube in the top. You can locate it from the vents on the bottom side of the plastic
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From: Chapel Hill, NC/Montreal, QC
1995 C36 AMG, 1998 C43 AMG
If the display doesn't have any errors, the temp sensor is the only other thing I could think of.
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98 C43
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From: Chapel Hill, NC/Montreal, QC
1995 C36 AMG, 1998 C43 AMG
If it is this temp sensor, then why does manual adjustments not work? For instance, if I am on EC and manual (not climate control), then shouldn't I be able to control the varying degrees of warmth? I can suspect this temp sensor if I was in auto mode, but my issue is even in manual mode.
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a faulty sampler blower motor or CCU is almost certainly it. more than likely the sampler blower motor. it's the cheapest, easiest thing to replace, too.
if your sensor is blown then it doesn't matter what fan speed you set it to. if it thinks it's 100 degrees in the car at all times, then it will only blow cool air unless you set it to HI on the temp setting.
if it thinks it's always 35 degrees in the car, it will always only blow HOT air unless you set the temp setting to LO
So, go all the way to the top and bottom temperature settings and see if it switches from hot to cold. I recommend starting with LO. If you start with HI it can take some time for the system to blow cool air because of how hot the heater core gets.
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98 C43
what he said.
a faulty sampler blower motor or CCU is almost certainly it. more than likely the sampler blower motor. it's the cheapest, easiest thing to replace, too.
if your sensor is blown then it doesn't matter what fan speed you set it to. if it thinks it's 100 degrees in the car at all times, then it will only blow cool air unless you set it to HI on the temp setting.
if it thinks it's always 35 degrees in the car, it will always only blow HOT air unless you set the temp setting to LO
So, go all the way to the top and bottom temperature settings and see if it switches from hot to cold. I recommend starting with LO. If you start with HI it can take some time for the system to blow cool air because of how hot the heater core gets.
a faulty sampler blower motor or CCU is almost certainly it. more than likely the sampler blower motor. it's the cheapest, easiest thing to replace, too.
if your sensor is blown then it doesn't matter what fan speed you set it to. if it thinks it's 100 degrees in the car at all times, then it will only blow cool air unless you set it to HI on the temp setting.
if it thinks it's always 35 degrees in the car, it will always only blow HOT air unless you set the temp setting to LO
So, go all the way to the top and bottom temperature settings and see if it switches from hot to cold. I recommend starting with LO. If you start with HI it can take some time for the system to blow cool air because of how hot the heater core gets.
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98 C43
Actually, I was envisioning a mixer, like what is found in many imports. For example, if I set it at 72F, doesn't it just allow x-amount of coolant and fresh air to formulate this temp, regardless of a reference point (ie. sampler blower motor)??
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98 C43
Just an update to this issue. I've changed out the duo valve, but the same issue is here. I can get the air either cold or HOT. There is no in between. If I set at 75F, it's the same as 50F, to get any heat, it needs to be set at HI. This is manual mode, not using AUTO. What else can it be? Sampler motor? I just don't see how a sampler motor matters because I am manually telling the car to output 75F. If I was doing climate control, then I can see the sampler motor playing a role. Stumped...
