Auto Climate Control...does It Work As Well As 'manual' Mode?

[Satz]

Hi all

I've noticed that if I leave my Climate Control in Auto mode during winter, it doesn't seem as warm in the car as when I use the 'manual' mode (Set at same temp).

Also... I've noticed that even in manual mode, the temperature of the air coming out of the vents is noticeably different at different times (even when the engine is already hot, and the outside temp is the same), so I have to increase the temp setting.

I thought I could just keep the temp setting at one setting, and it should keep the interior temp reasonably stable, regardless of whether it's first thing in the morning, or later in the night...

I don't use the AC even when in Auto mode. However i've tried with it on, and it makes no difference.

Do other owners find the same experience?

And do you know where the cabin temp sensor is?

many thanks

Satz

[cduluk]

Personally i find the "AUTO" function absolutely useless. It's never useful enough to respond to what i want in my head at any given time. I probably change the temperature and fan speed every 5 minutes or so, i'm VERY picky. And the passenger temp always has to be about 2 or 3 digits higher!

And the sensor's located on the lower dash panel right near your right knee.

[Satz]

Thanks cduluk

do you know if there's a sunlight/UV sensor linked in to the Climate Control?

According to my service manager there isn't, which I find hard to believe.

He says there's just the external temp sensor and the in-cabin temp sensor.

cheers

Satz

[rx350guy]

Agree that the 'auto' cabin climate control is worthless. I had it on for a few days after I bought the car because that's what the dealer recommended, but it never seemed to monitor and control the interior temperature very well, so I have been using the manual functions ever since..

[Satz]

it's really not very good. Just then I drove to somewhere on the way to work and set the Auto CC to 23.5C.

It seemed to be warming up nicely and was stable.

Then I parked the car for 10 minutes. Got in again and drove off, but this time it was cool air coming through. I had to increase the setting to 25C to get a similar warmth

:(

Does anyone know if there is a sunlight sensor, and where it's located? I want to check that it's not obstructed or dirty

cheers

Satz

[cduluk]

There is an ambient light sensor on the dash top, a few inches from where the windshield meets the dash. It's at the left edge of the thin vent for the defroster. Little dome frosted plastic looking thing.

However it only works for the auto headlights... not for the A/C (which is an AMAZING idea actually!!!).

[Satz]

oh no! I should patent that idea then!

:)

Actually my old 2007 Mazda CX7 and my 2007 VW GTI both used sunlight sensors as part of their Climate Control. The sunlight sensor would change the airflow depending on how much sunlight was coming in (and hence warming the interior)

It's a bit concerning that such an expensive car as the RX350 doesn't have that...

[jaswood]

Hi all

I've noticed that if I leave my Climate Control in Auto mode during winter, it doesn't seem as warm in the car as when I use the 'manual' mode (Set at same temp).

Also... I've noticed that even in manual mode, the temperature of the air coming out of the vents is noticeably different at different times (even when the engine is already hot, and the outside temp is the same), so I have to increase the temp setting.

I thought I could just keep the temp setting at one setting, and it should keep the interior temp reasonably stable, regardless of whether it's first thing in the morning, or later in the night...

I don't use the AC even when in Auto mode. However i've tried with it on, and it makes no difference.

Do other owners find the same experience?

And do you know where the cabin temp sensor is?

many thanks

Satz

Goggle for:

lexus "climate control" c-best

Or:

Lexus "climate control" wwest

[jaswood]

it's really not very good. Just then I drove to somewhere on the way to work and set the Auto CC to 23.5C.

It seemed to be warming up nicely and was stable.

Then I parked the car for 10 minutes. Got in again and drove off, but this time it was cool air coming through. I had to increase the setting to 25C to get a similar warmth

:(

Does anyone know if there is a sunlight sensor, and where it's located? I want to check that it's not obstructed or dirty

cheers

Satz

Once the cabin temperature rises to, or very near, your temperature setpoint it will automatically switch into cooling mode. Airflow primarily via the dash outlets, coolish and DRY discomforting airflow.

[lemon]

There is an ambient light sensor on the dash top, a few inches from where the windshield meets the dash. It's at the left edge of the thin vent for the defroster. Little dome frosted plastic looking thing.

However it only works for the auto headlights... not for the A/C (which is an AMAZING idea actually!!!).

That actually functions as both. It's an ambient light sensor for the headlights and a sun sensor for the climate control.

***edit***

Just flipping through the service manual - I shouldn't say it functions as both - it seems that there are two sensors there - one for the light control and one for the amount of sunlight. Per the shop manual, it's actually called a 'solar sensor'.

***edit part 2***

THe solar sensor actually has a left and right side (driver / passenger) in addition to the ambient light sensor for the headlights. These are all in the one sensor on top of the dash.

[klonny]

climate control...the one poster said it best..dry and discomfort...it seems to ALWAYS blow from the dash and doesn't automatically switch around feet...dash etc.

it just sucks, either learn to accept it or dump this miserable vehicle.

[LEXIRX330]

climate control...the one poster said it best..dry and discomfort...it seems to ALWAYS blow from the dash and doesn't automatically switch around feet...dash etc.

it just sucks, either learn to accept it or dump this miserable vehicle.

Hey klonny if it is such a miserable vehicle then get rid of it. Personally I find the auto climate works just as well as any other auto climate control I have had in any other car. My GX is better than my RX was but I think it is the position of the vents. The BMW and Mercedes climate features are about the same as the Lexus. I actually find my self !Removed! with my settings on my GX than the X5...

[Satz]

I've finally had time to run some actual temp readings using a digital thermometer..

When I set the CC temp to 23C (auto) the temp at driver's seat, as well as rear seat is between 21-23C

However, in the cold mornings the system seems to overcompensate, resulting in temps around 25C

(it's mid-winter here with outside temps ranging from 0C - 14C)

However I do find the cool air blowing to be a nuisance as it gives one the impression of being colder (even if the actual air temp measured is around 23C)

Why can't the system just not blow at all, or blow to the windscreen/feet rather than blowing cool air to the face vents?

[jaswood]

I've finally had time to run some actual temp readings using a digital thermometer..

When I set the CC temp to 23C (auto) the temp at driver's seat, as well as rear seat is between 21-23C

However, in the cold mornings the system seems to overcompensate, resulting in temps around 25C

(it's mid-winter here with outside temps ranging from 0C - 14C)

However I do find the cool air blowing to be a nuisance as it gives one the impression of being colder (even if the actual air temp measured is around 23C)

Why can't the system just not blow at all, or blow to the windscreen/feet rather than blowing cool air to the face vents?

I always manually switch the system back into footwell mode when the human comfort equation tilts to the heating side.

There are 2 primary factors in providing human comfort, surrounding air temperature and sumation of radiant effects. Body "out-welling" IR radiation LOSS along with incoming radiation gain. In the wintertime the surrounding landscape will predominantly be COLD, giving your body the "shivers". Since the climate control cannot modify the body heat loss effects of that COLD landscape it compensates slightly by raising the cabin air temperature.

[Satz]

My system seems to be okay in the daytime (when cold outside), but it's at night when it seems to run too cold, at the same temp setting (23c).

The actual air temp measurement seems to be around 22c, whereas in the daytime it's closer to 23.5C

(these are with AC button switched off)

[BlueRu]

climate control...the one poster said it best..dry and discomfort...it seems to ALWAYS blow from the dash and doesn't automatically switch around feet...dash etc.

it just sucks, either learn to accept it or dump this miserable vehicle.

Well klonny, have you dumped your Lexus? Or are you just wanting to spread your misery on this forum without the facts, which are that you bought a used Lexus that now has over 100,000 miles and you don't like some of the original features of the car. Next time you buy a car, how about test driving it and getting a certified pre-owned Lexus?

A quote that was totally meant for you follows:

"WAAAAAAAH!!! I have 100,000 miles on my car and I have to fix something! ROFLMAO!"

[SW03ES]

I understand your frustration with this poster Blue, but resurrecting an old finished thread with what really amounts to flamebait isn't the right approach. Best to let sleeping dogs lie.

You're new here so just a friendly warning, but that kind of thing can put your account in jeopardy.