I agree with you Brian, this feature drives me nuts. It's only under
extreme conditions that you would want to kick the A/C on in order to help with
removing the moisture from the inside of the windshield.
This was also added I believe in part to people not turning on their A/C
in the winter time and causing the seals in the A/C system to crack and ruin the
system. My Acura Integra doesn't have this feature and I usually turn the A/C on
once a month and have never had any problems with the system for 11 years now.
My mother's 99 Accord had this stupid feature, luckily Honda had built
in a feature to enable and disable it (Not sure if the current generation Accord
have the ability to turn it off).


Nick


On Thu, 26 Jan 2006 11:29:22 GMT, Brian Nystrom <brian.nystrom@verizon.net>
wrote:

>hyundaitech wrote:
>> Two possible reasons:
>> 1. The a/c was left on.
>> 2. The mode switch is set to defrost. A/C will greatly improve defroster
>> efficiency.
>
>"Defogger" yes, "defroster" no.
>
>The A/C dehumidifies that air coming through the vents, which does help
>to remove MOISTURE from the INSIDE of the windshield. OTOH, if you have
>snow/ice/frost on the OUTSIDE of the windshield, having the A/C on
>REDUCES the system's ability to melt it, since it lowers the temperature
>of the air coming through the vents and increases the the time it takes
>for the air to get warm. In the winter, it just plain sucks!
>
>Unfortunately, '01 and up US-spec Elantras have this dubious "feature"
>built in. On '01-'03 cars, snipping a single wire allows for completely
>independent A/C control, using the A/C switch. On '05 and up Elantras,
>the new control module prevents that simple modification. That's why I
>installed a switch in the A/C line that allows me to manually turn off
>the compressor when I need maximum efficiency from the defroster or when
>I prefer to clear fog from the windshield with heat, rather than cool,
>dry air. It also increases my gas mileage when using the defroster.
>
>BTW, when the heater control is set to defog/defrost, the A/C button is
>bypassed. Although pushing it will turn the light on and off, the
>compressor runs regardless. Interestingly, on Canadian-spec cars, the
>A/C switch CAN be used to turn the compressor on and of in defog/defrost
>mode.
>
>I have heard that this stupid system is now mandated by the DOT for all
>cars sold in the US that are equipped with A/C. Considering that it was
>something that could be done manually when necessary, it seems like a
>step backward and just another pointless attempt to idiot-proof cars.

 

almost all cars now turn the ac on when in defrost mode, some just do not
turn on the ac light...



"Nick" <npolite@NOSPAMMONKEYS.yahoo.com> wrote in message
news:65mht1pc3t6dl805bbqi63rs84e8pis9r6@4ax.com...
> I agree with you Brian, this feature drives me nuts. It's only under
> extreme conditions that you would want to kick the A/C on in order to help
> with
> removing the moisture from the inside of the windshield.
> This was also added I believe in part to people not turning on their A/C
> in the winter time and causing the seals in the A/C system to crack and
> ruin the
> system. My Acura Integra doesn't have this feature and I usually turn the
> A/C on
> once a month and have never had any problems with the system for 11 years
> now.
> My mother's 99 Accord had this stupid feature, luckily Honda had built
> in a feature to enable and disable it (Not sure if the current generation
> Accord
> have the ability to turn it off).
>
>
> Nick
>
>
> On Thu, 26 Jan 2006 11:29:22 GMT, Brian Nystrom
> <brian.nystrom@verizon.net>
> wrote:
>
>>hyundaitech wrote:
>>> Two possible reasons:
>>> 1. The a/c was left on.
>>> 2. The mode switch is set to defrost. A/C will greatly improve
>>> defroster
>>> efficiency.
>>
>>"Defogger" yes, "defroster" no.
>>
>>The A/C dehumidifies that air coming through the vents, which does help
>>to remove MOISTURE from the INSIDE of the windshield. OTOH, if you have
>>snow/ice/frost on the OUTSIDE of the windshield, having the A/C on
>>REDUCES the system's ability to melt it, since it lowers the temperature
>>of the air coming through the vents and increases the the time it takes
>>for the air to get warm. In the winter, it just plain sucks!
>>
>>Unfortunately, '01 and up US-spec Elantras have this dubious "feature"
>>built in. On '01-'03 cars, snipping a single wire allows for completely
>>independent A/C control, using the A/C switch. On '05 and up Elantras,
>>the new control module prevents that simple modification. That's why I
>>installed a switch in the A/C line that allows me to manually turn off
>>the compressor when I need maximum efficiency from the defroster or when
>>I prefer to clear fog from the windshield with heat, rather than cool,
>>dry air. It also increases my gas mileage when using the defroster.
>>
>>BTW, when the heater control is set to defog/defrost, the A/C button is
>>bypassed. Although pushing it will turn the light on and off, the
>>compressor runs regardless. Interestingly, on Canadian-spec cars, the
>>A/C switch CAN be used to turn the compressor on and of in defog/defrost
>>mode.
>>
>>I have heard that this stupid system is now mandated by the DOT for all
>>cars sold in the US that are equipped with A/C. Considering that it was
>>something that could be done manually when necessary, it seems like a
>>step backward and just another pointless attempt to idiot-proof cars.

 

almost all cars now turn the ac on when in defrost mode, some just do not
turn on the ac light...



"Nick" <npolite@NOSPAMMONKEYS.yahoo.com> wrote in message
news:65mht1pc3t6dl805bbqi63rs84e8pis9r6@4ax.com...
> I agree with you Brian, this feature drives me nuts. It's only under
> extreme conditions that you would want to kick the A/C on in order to help
> with
> removing the moisture from the inside of the windshield.
> This was also added I believe in part to people not turning on their A/C
> in the winter time and causing the seals in the A/C system to crack and
> ruin the
> system. My Acura Integra doesn't have this feature and I usually turn the
> A/C on
> once a month and have never had any problems with the system for 11 years
> now.
> My mother's 99 Accord had this stupid feature, luckily Honda had built
> in a feature to enable and disable it (Not sure if the current generation
> Accord
> have the ability to turn it off).
>
>
> Nick
>
>
> On Thu, 26 Jan 2006 11:29:22 GMT, Brian Nystrom
> <brian.nystrom@verizon.net>
> wrote:
>
>>hyundaitech wrote:
>>> Two possible reasons:
>>> 1. The a/c was left on.
>>> 2. The mode switch is set to defrost. A/C will greatly improve
>>> defroster
>>> efficiency.
>>
>>"Defogger" yes, "defroster" no.
>>
>>The A/C dehumidifies that air coming through the vents, which does help
>>to remove MOISTURE from the INSIDE of the windshield. OTOH, if you have
>>snow/ice/frost on the OUTSIDE of the windshield, having the A/C on
>>REDUCES the system's ability to melt it, since it lowers the temperature
>>of the air coming through the vents and increases the the time it takes
>>for the air to get warm. In the winter, it just plain sucks!
>>
>>Unfortunately, '01 and up US-spec Elantras have this dubious "feature"
>>built in. On '01-'03 cars, snipping a single wire allows for completely
>>independent A/C control, using the A/C switch. On '05 and up Elantras,
>>the new control module prevents that simple modification. That's why I
>>installed a switch in the A/C line that allows me to manually turn off
>>the compressor when I need maximum efficiency from the defroster or when
>>I prefer to clear fog from the windshield with heat, rather than cool,
>>dry air. It also increases my gas mileage when using the defroster.
>>
>>BTW, when the heater control is set to defog/defrost, the A/C button is
>>bypassed. Although pushing it will turn the light on and off, the
>>compressor runs regardless. Interestingly, on Canadian-spec cars, the
>>A/C switch CAN be used to turn the compressor on and of in defog/defrost
>>mode.
>>
>>I have heard that this stupid system is now mandated by the DOT for all
>>cars sold in the US that are equipped with A/C. Considering that it was
>>something that could be done manually when necessary, it seems like a
>>step backward and just another pointless attempt to idiot-proof cars.

 

almost all cars now turn the ac on when in defrost mode, some just do not
turn on the ac light...



"Nick" <npolite@NOSPAMMONKEYS.yahoo.com> wrote in message
news:65mht1pc3t6dl805bbqi63rs84e8pis9r6@4ax.com...
> I agree with you Brian, this feature drives me nuts. It's only under
> extreme conditions that you would want to kick the A/C on in order to help
> with
> removing the moisture from the inside of the windshield.
> This was also added I believe in part to people not turning on their A/C
> in the winter time and causing the seals in the A/C system to crack and
> ruin the
> system. My Acura Integra doesn't have this feature and I usually turn the
> A/C on
> once a month and have never had any problems with the system for 11 years
> now.
> My mother's 99 Accord had this stupid feature, luckily Honda had built
> in a feature to enable and disable it (Not sure if the current generation
> Accord
> have the ability to turn it off).
>
>
> Nick
>
>
> On Thu, 26 Jan 2006 11:29:22 GMT, Brian Nystrom
> <brian.nystrom@verizon.net>
> wrote:
>
>>hyundaitech wrote:
>>> Two possible reasons:
>>> 1. The a/c was left on.
>>> 2. The mode switch is set to defrost. A/C will greatly improve
>>> defroster
>>> efficiency.
>>
>>"Defogger" yes, "defroster" no.
>>
>>The A/C dehumidifies that air coming through the vents, which does help
>>to remove MOISTURE from the INSIDE of the windshield. OTOH, if you have
>>snow/ice/frost on the OUTSIDE of the windshield, having the A/C on
>>REDUCES the system's ability to melt it, since it lowers the temperature
>>of the air coming through the vents and increases the the time it takes
>>for the air to get warm. In the winter, it just plain sucks!
>>
>>Unfortunately, '01 and up US-spec Elantras have this dubious "feature"
>>built in. On '01-'03 cars, snipping a single wire allows for completely
>>independent A/C control, using the A/C switch. On '05 and up Elantras,
>>the new control module prevents that simple modification. That's why I
>>installed a switch in the A/C line that allows me to manually turn off
>>the compressor when I need maximum efficiency from the defroster or when
>>I prefer to clear fog from the windshield with heat, rather than cool,
>>dry air. It also increases my gas mileage when using the defroster.
>>
>>BTW, when the heater control is set to defog/defrost, the A/C button is
>>bypassed. Although pushing it will turn the light on and off, the
>>compressor runs regardless. Interestingly, on Canadian-spec cars, the
>>A/C switch CAN be used to turn the compressor on and of in defog/defrost
>>mode.
>>
>>I have heard that this stupid system is now mandated by the DOT for all
>>cars sold in the US that are equipped with A/C. Considering that it was
>>something that could be done manually when necessary, it seems like a
>>step backward and just another pointless attempt to idiot-proof cars.

 

Bob wrote:
> "Brian Nystrom" <brian.nystrom@verizon.net> wrote in message
> news:mo2Cf.5506$Jn1.3358@trndny01...
>
>>The A/C dehumidifies that air coming through the vents, which does help to
>>remove MOISTURE from the INSIDE of the windshield. OTOH, if you have
>>snow/ice/frost on the OUTSIDE of the windshield, having the A/C on REDUCES
>>the system's ability to melt it, since it lowers the temperature of the
>>air coming through the vents and increases the the time it takes for the
>>air to get warm. In the winter, it just plain sucks!
>>
>
> Actually, the system is smarter than you might think. There's a temperature
> sensor on the evaporator that inhibits the compressor when the evaporator is
> close to 0 degrees C. If it's close enough to freezing outside that you have
> ice or snow on the windshield, then the compressor is not likely to be
> running.

On would think that would be the case, but you can feel the compressor
kick in and feel the temp difference in the air.

> Even if it is, the temperature difference as a result of it running
> is pretty small. All you are trying to do to melt the ice / frost is to get
> the temp. of the glass a little above freezing - that's while you are still
> parked.

The problems is that it's NOT just an issue when you're sitting still.
Last winter, I got caught in a situation where I couldn't keep freezing
drizzle off the windshield, even with the heat set and fan set to max
with the defroster on. The temp wasn't much below freezing at the time.
I've never had that problem in a car before.

> After you are moving, and if the temp. of the air passing over the
> evaporator is warm enough, the fact that the air is dried helps keep the
> inside of the windshield clear.

Heat keeps the inside of the windshield clear quite effectively unless
we've just come in from some sweaty activity like X/C skiing. If I need
the A/C to reduce humidity in the car, I can turn it on myself.

The point is that this should be an option that's controlled by the
driver, not something that's imposed by the heater control module.

 

Bob wrote:
> "Brian Nystrom" <brian.nystrom@verizon.net> wrote in message
> news:mo2Cf.5506$Jn1.3358@trndny01...
>
>>The A/C dehumidifies that air coming through the vents, which does help to
>>remove MOISTURE from the INSIDE of the windshield. OTOH, if you have
>>snow/ice/frost on the OUTSIDE of the windshield, having the A/C on REDUCES
>>the system's ability to melt it, since it lowers the temperature of the
>>air coming through the vents and increases the the time it takes for the
>>air to get warm. In the winter, it just plain sucks!
>>
>
> Actually, the system is smarter than you might think. There's a temperature
> sensor on the evaporator that inhibits the compressor when the evaporator is
> close to 0 degrees C. If it's close enough to freezing outside that you have
> ice or snow on the windshield, then the compressor is not likely to be
> running.

On would think that would be the case, but you can feel the compressor
kick in and feel the temp difference in the air.

> Even if it is, the temperature difference as a result of it running
> is pretty small. All you are trying to do to melt the ice / frost is to get
> the temp. of the glass a little above freezing - that's while you are still
> parked.

The problems is that it's NOT just an issue when you're sitting still.
Last winter, I got caught in a situation where I couldn't keep freezing
drizzle off the windshield, even with the heat set and fan set to max
with the defroster on. The temp wasn't much below freezing at the time.
I've never had that problem in a car before.

> After you are moving, and if the temp. of the air passing over the
> evaporator is warm enough, the fact that the air is dried helps keep the
> inside of the windshield clear.

Heat keeps the inside of the windshield clear quite effectively unless
we've just come in from some sweaty activity like X/C skiing. If I need
the A/C to reduce humidity in the car, I can turn it on myself.

The point is that this should be an option that's controlled by the
driver, not something that's imposed by the heater control module.

 

Bob wrote:
> "Brian Nystrom" <brian.nystrom@verizon.net> wrote in message
> news:mo2Cf.5506$Jn1.3358@trndny01...
>
>>The A/C dehumidifies that air coming through the vents, which does help to
>>remove MOISTURE from the INSIDE of the windshield. OTOH, if you have
>>snow/ice/frost on the OUTSIDE of the windshield, having the A/C on REDUCES
>>the system's ability to melt it, since it lowers the temperature of the
>>air coming through the vents and increases the the time it takes for the
>>air to get warm. In the winter, it just plain sucks!
>>
>
> Actually, the system is smarter than you might think. There's a temperature
> sensor on the evaporator that inhibits the compressor when the evaporator is
> close to 0 degrees C. If it's close enough to freezing outside that you have
> ice or snow on the windshield, then the compressor is not likely to be
> running.

On would think that would be the case, but you can feel the compressor
kick in and feel the temp difference in the air.

> Even if it is, the temperature difference as a result of it running
> is pretty small. All you are trying to do to melt the ice / frost is to get
> the temp. of the glass a little above freezing - that's while you are still
> parked.

The problems is that it's NOT just an issue when you're sitting still.
Last winter, I got caught in a situation where I couldn't keep freezing
drizzle off the windshield, even with the heat set and fan set to max
with the defroster on. The temp wasn't much below freezing at the time.
I've never had that problem in a car before.

> After you are moving, and if the temp. of the air passing over the
> evaporator is warm enough, the fact that the air is dried helps keep the
> inside of the windshield clear.

Heat keeps the inside of the windshield clear quite effectively unless
we've just come in from some sweaty activity like X/C skiing. If I need
the A/C to reduce humidity in the car, I can turn it on myself.

The point is that this should be an option that's controlled by the
driver, not something that's imposed by the heater control module.

 

Nick wrote:
> I agree with you Brian, this feature drives me nuts. It's only under
> extreme conditions that you would want to kick the A/C on in order to help with
> removing the moisture from the inside of the windshield.

The other thing that I hate about it is that if you put on the defroster
to clear the windshield, then switch to heat to warm up the rest of the
car, the moisture on the condenser gets pumped into the car, causing
everything to fog up again. That's why I prefer to use heat to keep the
inside of the windows clear whenever possible.

> This was also added I believe in part to people not turning on their A/C
> in the winter time and causing the seals in the A/C system to crack and ruin the
> system. My Acura Integra doesn't have this feature and I usually turn the A/C on
> once a month and have never had any problems with the system for 11 years now.

That could be. This is the first car I've owned with A/C and I rarely
use it, largely because of the gas mileage penalty of using it. I find
the system to be far stronger than it needs to be and I wisk there was a
way to install an under-drive pulley to reduce the drag on the engine
when it's running.

One thing that a lot of Elantra owners have learned the hard way is that
the A/C heat exchanger is mounted in a position where it's vulnerable to
damage from stones and other debris kicked up from the road. Like many,
I've added screen behind the grill to prevent damage.

> My mother's 99 Accord had this stupid feature, luckily Honda had built
> in a feature to enable and disable it (Not sure if the current generation Accord
> have the ability to turn it off).

My understanding is the automatic system is DOT mandated for '05 and
newer vehicles.

For anyone interested in learning more about these and other issues and
modifications to the Elantra, the Elantra Club Website is a treasure
trove of knowledge. http://elantragtclub.tripod.com/elantra/

>
> On Thu, 26 Jan 2006 11:29:22 GMT, Brian Nystrom <brian.nystrom@verizon.net>
> wrote:
>
>
>>hyundaitech wrote:
>>
>>>Two possible reasons:
>>>1. The a/c was left on.
>>>2. The mode switch is set to defrost. A/C will greatly improve defroster
>>>efficiency.
>>
>>"Defogger" yes, "defroster" no.
>>
>>The A/C dehumidifies that air coming through the vents, which does help
>>to remove MOISTURE from the INSIDE of the windshield. OTOH, if you have
>>snow/ice/frost on the OUTSIDE of the windshield, having the A/C on
>>REDUCES the system's ability to melt it, since it lowers the temperature
>>of the air coming through the vents and increases the the time it takes
>>for the air to get warm. In the winter, it just plain sucks!
>>
>>Unfortunately, '01 and up US-spec Elantras have this dubious "feature"
>>built in. On '01-'03 cars, snipping a single wire allows for completely
>>independent A/C control, using the A/C switch. On '05 and up Elantras,
>>the new control module prevents that simple modification. That's why I
>>installed a switch in the A/C line that allows me to manually turn off
>>the compressor when I need maximum efficiency from the defroster or when
>>I prefer to clear fog from the windshield with heat, rather than cool,
>>dry air. It also increases my gas mileage when using the defroster.
>>
>>BTW, when the heater control is set to defog/defrost, the A/C button is
>>bypassed. Although pushing it will turn the light on and off, the
>>compressor runs regardless. Interestingly, on Canadian-spec cars, the
>>A/C switch CAN be used to turn the compressor on and of in defog/defrost
>>mode.
>>
>>I have heard that this stupid system is now mandated by the DOT for all
>>cars sold in the US that are equipped with A/C. Considering that it was
>>something that could be done manually when necessary, it seems like a
>>step backward and just another pointless attempt to idiot-proof cars.

 

Nick wrote:
> I agree with you Brian, this feature drives me nuts. It's only under
> extreme conditions that you would want to kick the A/C on in order to help with
> removing the moisture from the inside of the windshield.

The other thing that I hate about it is that if you put on the defroster
to clear the windshield, then switch to heat to warm up the rest of the
car, the moisture on the condenser gets pumped into the car, causing
everything to fog up again. That's why I prefer to use heat to keep the
inside of the windows clear whenever possible.

> This was also added I believe in part to people not turning on their A/C
> in the winter time and causing the seals in the A/C system to crack and ruin the
> system. My Acura Integra doesn't have this feature and I usually turn the A/C on
> once a month and have never had any problems with the system for 11 years now.

That could be. This is the first car I've owned with A/C and I rarely
use it, largely because of the gas mileage penalty of using it. I find
the system to be far stronger than it needs to be and I wisk there was a
way to install an under-drive pulley to reduce the drag on the engine
when it's running.

One thing that a lot of Elantra owners have learned the hard way is that
the A/C heat exchanger is mounted in a position where it's vulnerable to
damage from stones and other debris kicked up from the road. Like many,
I've added screen behind the grill to prevent damage.

> My mother's 99 Accord had this stupid feature, luckily Honda had built
> in a feature to enable and disable it (Not sure if the current generation Accord
> have the ability to turn it off).

My understanding is the automatic system is DOT mandated for '05 and
newer vehicles.

For anyone interested in learning more about these and other issues and
modifications to the Elantra, the Elantra Club Website is a treasure
trove of knowledge. http://elantragtclub.tripod.com/elantra/

>
> On Thu, 26 Jan 2006 11:29:22 GMT, Brian Nystrom <brian.nystrom@verizon.net>
> wrote:
>
>
>>hyundaitech wrote:
>>
>>>Two possible reasons:
>>>1. The a/c was left on.
>>>2. The mode switch is set to defrost. A/C will greatly improve defroster
>>>efficiency.
>>
>>"Defogger" yes, "defroster" no.
>>
>>The A/C dehumidifies that air coming through the vents, which does help
>>to remove MOISTURE from the INSIDE of the windshield. OTOH, if you have
>>snow/ice/frost on the OUTSIDE of the windshield, having the A/C on
>>REDUCES the system's ability to melt it, since it lowers the temperature
>>of the air coming through the vents and increases the the time it takes
>>for the air to get warm. In the winter, it just plain sucks!
>>
>>Unfortunately, '01 and up US-spec Elantras have this dubious "feature"
>>built in. On '01-'03 cars, snipping a single wire allows for completely
>>independent A/C control, using the A/C switch. On '05 and up Elantras,
>>the new control module prevents that simple modification. That's why I
>>installed a switch in the A/C line that allows me to manually turn off
>>the compressor when I need maximum efficiency from the defroster or when
>>I prefer to clear fog from the windshield with heat, rather than cool,
>>dry air. It also increases my gas mileage when using the defroster.
>>
>>BTW, when the heater control is set to defog/defrost, the A/C button is
>>bypassed. Although pushing it will turn the light on and off, the
>>compressor runs regardless. Interestingly, on Canadian-spec cars, the
>>A/C switch CAN be used to turn the compressor on and of in defog/defrost
>>mode.
>>
>>I have heard that this stupid system is now mandated by the DOT for all
>>cars sold in the US that are equipped with A/C. Considering that it was
>>something that could be done manually when necessary, it seems like a
>>step backward and just another pointless attempt to idiot-proof cars.

 

Nick wrote:
> I agree with you Brian, this feature drives me nuts. It's only under
> extreme conditions that you would want to kick the A/C on in order to help with
> removing the moisture from the inside of the windshield.

The other thing that I hate about it is that if you put on the defroster
to clear the windshield, then switch to heat to warm up the rest of the
car, the moisture on the condenser gets pumped into the car, causing
everything to fog up again. That's why I prefer to use heat to keep the
inside of the windows clear whenever possible.

> This was also added I believe in part to people not turning on their A/C
> in the winter time and causing the seals in the A/C system to crack and ruin the
> system. My Acura Integra doesn't have this feature and I usually turn the A/C on
> once a month and have never had any problems with the system for 11 years now.

That could be. This is the first car I've owned with A/C and I rarely
use it, largely because of the gas mileage penalty of using it. I find
the system to be far stronger than it needs to be and I wisk there was a
way to install an under-drive pulley to reduce the drag on the engine
when it's running.

One thing that a lot of Elantra owners have learned the hard way is that
the A/C heat exchanger is mounted in a position where it's vulnerable to
damage from stones and other debris kicked up from the road. Like many,
I've added screen behind the grill to prevent damage.

> My mother's 99 Accord had this stupid feature, luckily Honda had built
> in a feature to enable and disable it (Not sure if the current generation Accord
> have the ability to turn it off).

My understanding is the automatic system is DOT mandated for '05 and
newer vehicles.

For anyone interested in learning more about these and other issues and
modifications to the Elantra, the Elantra Club Website is a treasure
trove of knowledge. http://elantragtclub.tripod.com/elantra/

>
> On Thu, 26 Jan 2006 11:29:22 GMT, Brian Nystrom <brian.nystrom@verizon.net>
> wrote:
>
>
>>hyundaitech wrote:
>>
>>>Two possible reasons:
>>>1. The a/c was left on.
>>>2. The mode switch is set to defrost. A/C will greatly improve defroster
>>>efficiency.
>>
>>"Defogger" yes, "defroster" no.
>>
>>The A/C dehumidifies that air coming through the vents, which does help
>>to remove MOISTURE from the INSIDE of the windshield. OTOH, if you have
>>snow/ice/frost on the OUTSIDE of the windshield, having the A/C on
>>REDUCES the system's ability to melt it, since it lowers the temperature
>>of the air coming through the vents and increases the the time it takes
>>for the air to get warm. In the winter, it just plain sucks!
>>
>>Unfortunately, '01 and up US-spec Elantras have this dubious "feature"
>>built in. On '01-'03 cars, snipping a single wire allows for completely
>>independent A/C control, using the A/C switch. On '05 and up Elantras,
>>the new control module prevents that simple modification. That's why I
>>installed a switch in the A/C line that allows me to manually turn off
>>the compressor when I need maximum efficiency from the defroster or when
>>I prefer to clear fog from the windshield with heat, rather than cool,
>>dry air. It also increases my gas mileage when using the defroster.
>>
>>BTW, when the heater control is set to defog/defrost, the A/C button is
>>bypassed. Although pushing it will turn the light on and off, the
>>compressor runs regardless. Interestingly, on Canadian-spec cars, the
>>A/C switch CAN be used to turn the compressor on and of in defog/defrost
>>mode.
>>
>>I have heard that this stupid system is now mandated by the DOT for all
>>cars sold in the US that are equipped with A/C. Considering that it was
>>something that could be done manually when necessary, it seems like a
>>step backward and just another pointless attempt to idiot-proof cars.