Go Back   Club Lexus Forums > Lexus Model Forums > RX Models > RX - Second Generation
Sign in using an external account
Register Forgot Password?

'05 RX330 blows hot air inconsistently

Reply
 
 
 
 
Thread Tools Search this Thread Display Modes
Old 10-25-11, 06:12 PM   #1
quantfutur
Rookie
Trader Score: (0)
 
Join Date: Feb 2011
Location: MA
Posts: 99
Default '05 RX330 blows hot air inconsistently

My '05 RX330 has a problem with the heater. In MA, about 50-58oF and trying to put the heater at 80-HIGH either on auto or A/C. Sometimes it blows hot air and then switches to cold or gets really hot, or just runs cold for a bit. Checked coolant, it was low so filled it this evening. Didn't seem to make a difference. Had tuneup 15k miles ago so coolant has not been filled to my knowledge in a year.....

Seems 'intuitively' like some sensor is off, the one which measures the temperature in the car and filters mixture of hot and cold to achieve the selected manual temperature. But when I manually select to "HIGH" I thought this should always blow hot air no matter the temperature in the car.... ? [In the past in summer if I wanted a bit of heat in the car I would have to put it on HIGH to get some warm air, as obviously the sensor thought the car was 80+. E.g., HIGH setting always produced heat.]

Suggestions? Thanks.
This ad is not displayed to registered members.
Register your free account today and become a member on Club Lexus!

Last edited by quantfutur; 10-25-11 at 07:28 PM..
quantfutur is offline   Reply With Quote
Old 10-25-11, 07:34 PM   #2
ac921ol
Lead Lap
Trader Score: (1)
 
Join Date: Mar 2010
Location: VA
Posts: 612
Default

any cels? What about on the very cold setting does this happen?
ac921ol is offline   Reply With Quote
Old 10-25-11, 07:44 PM   #3
quantfutur
Rookie
Trader Score: (0)
 
Join Date: Feb 2011
Location: MA
Posts: 99
Default

P.S. the temperature (cool or hot) is exactly the same on both driver and passenger sides. So that if it is blowing cold when set on HIGH, both sides are blowing the cold air.
quantfutur is offline   Reply With Quote
Old 10-25-11, 07:48 PM   #4
MC5Wes
Registered User
Trader Score: (0)
 
Join Date: Dec 2010
Location: Nevada
Posts: 471
Default Air Conditioning Problems

quantfutur
ac921ol
Welcome to Clublexus. Just a couple of tips for you and any other new members.

Search Google prior to posting any questions. If you have no luck.

Use the search function on Clublexus. It is outstanding. When your looking for help. Look in all of the Lexus models. They all use the same systems.

Also every question you could possibly think of asking. Ever. Has already been answered.

If your looking into how your car operates. The owners manual for your car is online at this Lexus web site.

https://secure.drivers.lexus.com/lexusdrivers/home

It also has a great search functions.

If after all this you have no luck. And want to start a new topic. State which type of car and equipment you have installed. For example the year. Is it a 330 or 350. FWD or AWD. Is it a Lexus that was sold in the states or overseas. Mark Levinson or Premium Stereo. Navigation. Rear Entertainment. Does the system work and your only getting a warning. Things like that.

On your Air Conditioning system. There has been numerous postings about heater and A/C air flow and temperature problems. A 1 minute search of this web page. Showed these postings.

Again. When your looking for help. Look in all of the Lexus models. They all use the same systems.

http://www.clublexus.com/forums/rx-s...ch-advice.html

http://www.clublexus.com/forums/rx-f...-cold-air.html

http://www.clublexus.com/forums/gs-s...vo-motors.html

Good luck and welcome to Club Lexus.
MC5Wes is offline   Reply With Quote
Old 10-25-11, 07:54 PM   #5
quantfutur
Rookie
Trader Score: (0)
 
Join Date: Feb 2011
Location: MA
Posts: 99
Default

Quote:
Originally Posted by ac921ol View Post
any cels? What about on the very cold setting does this happen?

Not sure what are 'cels'; sorry. On cold setting it runs cold. Problem is getting any heat. Heat is very inconsistent. Should be giving me heat (based on past performance) from 80+ manual setting but certainly when manual HIGH is set. Sometimes it does, sometimes it doesn't... !
quantfutur is offline   Reply With Quote
Old 10-25-11, 08:00 PM   #6
quantfutur
Rookie
Trader Score: (0)
 
Join Date: Feb 2011
Location: MA
Posts: 99
Default

Quote:
Originally Posted by MC5Wes View Post
quantfutur
ac921ol
Welcome to Clublexus. Just a couple of tips for you and any other new members.

Search Google prior to posting any questions. If you have no luck.

Use the search function on Clublexus. It is outstanding. When your looking for help. Look in all of the Lexus models. They all use the same systems.

Also every question you could possibly think of asking. Ever. Has already been answered.

If your looking into how your car operates. The owners manual for your car is online at this Lexus web site.

https://secure.drivers.lexus.com/lexusdrivers/home

It also has a great search functions.

If after all this you have no luck. And want to start a new topic. State which type of car and equipment you have installed. For example the year. Is it a 330 or 350. FWD or AWD. Is it a Lexus that was sold in the states or overseas. Mark Levinson or Premium Stereo. Navigation. Rear Entertainment. Does the system work and your only getting a warning. Things like that.

On your Air Conditioning system. There has been numerous postings about heater and A/C air flow and temperature problems. A 1 minute search of this web page. Showed these postings.

Again. When your looking for help. Look in all of the Lexus models. They all use the same systems.

http://www.clublexus.com/forums/rx-s...ch-advice.html

http://www.clublexus.com/forums/rx-f...-cold-air.html

http://www.clublexus.com/forums/gs-s...vo-motors.html

Good luck and welcome to Club Lexus.

Thanks very much. I will search all the links you provided.
quantfutur is offline   Reply With Quote
Old 10-26-11, 03:11 PM   #7
gusar
Rookie
Trader Score: (0)
 
Join Date: Dec 2009
Location: Ontario
Posts: 99
Default

Quote:
Originally Posted by quantfutur View Post
My '05 RX330 has a problem with the heater. In MA, about 50-58oF and trying to put the heater at 80-HIGH either on auto or A/C. Sometimes it blows hot air and then switches to cold or gets really hot, or just runs cold for a bit. Checked coolant, it was low so filled it this evening. Didn't seem to make a difference. Had tuneup 15k miles ago so coolant has not been filled to my knowledge in a year.....

Seems 'intuitively' like some sensor is off, the one which measures the temperature in the car and filters mixture of hot and cold to achieve the selected manual temperature. But when I manually select to "HIGH" I thought this should always blow hot air no matter the temperature in the car.... ? [In the past in summer if I wanted a bit of heat in the car I would have to put it on HIGH to get some warm air, as obviously the sensor thought the car was 80+. E.g., HIGH setting always produced heat.]

Suggestions? Thanks.
Was it consistent with delivering cool air in summer (with AC off)?
My RX330 was not consistent and after a stop gave me warm air instead of cool (from outside). If AC was on, it always made it cold, but without AC - sometimes warm.
gusar is offline   Reply With Quote
Old 10-26-11, 10:01 PM   #8
quantfutur
Rookie
Trader Score: (0)
 
Join Date: Feb 2011
Location: MA
Posts: 99
Default

Quote:
Originally Posted by gusar View Post
Was it consistent with delivering cool air in summer (with AC off)?
My RX330 was not consistent and after a stop gave me warm air instead of cool (from outside). If AC was on, it always made it cold, but without AC - sometimes warm.

Yes, I believe it did deliver cool air in summer (manual had been set to 75 when it was running).. with the AC off. Gusar - what ended up being the problem for you, and how was it resolved? Thanks.
quantfutur is offline   Reply With Quote
Old 10-27-11, 07:47 AM   #9
gusar
Rookie
Trader Score: (0)
 
Join Date: Dec 2009
Location: Ontario
Posts: 99
Default

Quote:
Originally Posted by quantfutur View Post
Yes, I believe it did deliver cool air in summer (manual had been set to 75 when it was running).. with the AC off. Gusar - what ended up being the problem for you, and how was it resolved? Thanks.
Actually, my problem was not resolved. Just fall came
I think in my case something is not stable in the control block - vent door sometimes stop moving. Not often though. Now it works (heats).
Basically there are three areas for your problem to be potentially responsible:
1. Control block and temp. sensor
2. Servo motors/doors' mechanics/contacts
3. Clogged heater radiator(s).

I would bet on #1 or 2. If you can get access and see doors moving or stuck (when changing temp. setting), you may be closer to resolving the problem.

Last edited by gusar; 10-27-11 at 07:50 AM..
gusar is offline   Reply With Quote
Old 10-27-11, 04:25 PM   #10
quantfutur
Rookie
Trader Score: (0)
 
Join Date: Feb 2011
Location: MA
Posts: 99
Default

Gusar- thanks. I plan to take it to a local auto repair shop that deals with a/c issues rather than to the dealer, and will bring your list; make sense. Fan power is fine from what I can sense. Things improved a bit after I got the coolant back to level, but definitely a problem with the a/c.
quantfutur is offline   Reply With Quote
Old 10-27-11, 04:27 PM   #11
quantfutur
Rookie
Trader Score: (0)
 
Join Date: Feb 2011
Location: MA
Posts: 99
Default

Btw, are there separate temperature sensor for driver and passenger? If so, then may be possible to rule that out as I have both sides set at same temperature and both pushing cold air at times.....
quantfutur is offline   Reply With Quote
Old 10-28-11, 10:05 AM   #12
gusar
Rookie
Trader Score: (0)
 
Join Date: Dec 2009
Location: Ontario
Posts: 99
Default

Quote:
Originally Posted by quantfutur View Post
Btw, are there separate temperature sensor for driver and passenger? If so, then may be possible to rule that out as I have both sides set at same temperature and both pushing cold air at times.....
Never heard about two sensors. Sensor is placed at the driver's side above the driver's knees - small window there.

Good luck. Probably will cost you...

Last edited by gusar; 10-28-11 at 10:08 AM..
gusar is offline   Reply With Quote
Old 10-28-11, 01:23 PM   #13
MC5Wes
Registered User
Trader Score: (0)
 
Join Date: Dec 2010
Location: Nevada
Posts: 471
Default Servos

If your car is operating ok. Not overheating.

You probably have a problem with the air control servos. There are two of them. One for temp mixing and one for outside air.

If you look at the links I posted above. You will see pictures and a Do It Yourself thread.

http://lexus.sewellparts.com/accesso...2004/4620.html

All of the Lexus models use the same servos. I tried to fix mine in my RX300. But the problem came back. So I eneded up just changing both.
Attached Images
  
MC5Wes is offline   Reply With Quote
Old 10-28-11, 01:25 PM   #14
MC5Wes
Registered User
Trader Score: (0)
 
Join Date: Dec 2010
Location: Nevada
Posts: 471
Default Servos

They are located under the dash in the center console. Over on the passenger side.

Here is a picture of one taken apart.
Attached Images
 
MC5Wes is offline   Reply With Quote
Old 10-28-11, 08:05 PM   #15
quantfutur
Rookie
Trader Score: (0)
 
Join Date: Feb 2011
Location: MA
Posts: 99
Default

Quote:
Originally Posted by MC5Wes View Post
They are located under the dash in the center console. Over on the passenger side.

Here is a picture of one taken apart.
Thanks, MC5Wes.. Took the car to a mechanic today who looked at it briefly; he thinks it's either the thermostat, water pump (replaced 15k miles ago with timing belt), or a blocked heater core. Called another mechanic who was recommended and he said 9 times out of 10, flushing the heater core takes care of the problem. Big bucks if the heater core is leaking. I too thought it might be a servo; probably the cooling servo. What symptoms did you have that led you to the servo motors?

Will take it to the 2nd mechanic in a few days and get an assessment. From what I've read on this forum, repair/replacing the heater core is a huge job, so hoping it isn't that....
quantfutur is offline   Reply With Quote
Old 10-28-11, 08:05 PM
 
 
 
 
Reply

Similar Threads
Thread Thread Starter Forum Replies Last Post
Heat and climate control air routing screwed up. Studiogeek SC 400/300 5 11-02-14 08:17 PM
Heater blowing cold air and the air smell bad. karolek98 Performance & Maintenance 1 10-19-14 09:08 AM
Heat only coming from Driver's side, but Cold A/C works on both ddlaz RX - Second Generation 0 09-09-14 07:27 AM
Is your car's engine slow to warm up in the winter? mmarshall Car Chat 24 01-06-13 09:22 PM
2001 Rx300 heater problem khoab88 RX - First Generation 4 03-21-12 08:35 AM


Tags
330, ac, access, air, auto, blows, cold, core, heat, heater, hiter, hot, lexas, lexus, problem, produce, rx, rx330, time

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

Forum Jump

All times are GMT -7. The time now is 07:48 AM.

Join ClubLexus
Advertising


Copyright © 2000-2008 Internet Brands, Inc. All Rights Reserved
Privacy Policy | Disclaimer | Terms of Use | JOBS


Get all contact info