petersc400

Okay... I've read lots of posts regarding problems with heaters not working, etc. Check the fuses, heater control valve, etc. However, my problem appears to be unique: the climate control panel lights up, the AC works fine, but the fan speed only works on manual. As soon as I go to AUTO the fan speed disappears on the dial and there is no output of air. Back to manual and I get blower action but still no heat. I turned the defroster on last nite and got a cold blast of AC but no heat...eventually cleared the windshield but not totally at the bottom.

Oddly, the power antenna stopped working about the same time.... probably coincidence? The cigarette lighter works fine.... I'm taking it to my mech in two days but would appreciate any wisdom from the club as far as direction.... I'm praying it's not the climate control itself.

Thanks in advance.

O. L. T.

iTrader: (17)

- Issues with fan speed at any setting when using it manually?
- Did display show heat, but none came out at any setting auto or man?
- Can you force the heat on by opening the control valve manually? https://www.clublexus.com/forums/per...rol-valve.html

Fuses in kick panel should ALL be checked.

petersc400

Thanks for the quick reply;
The fan seems to work fine on manual setting in all positions (feet, face, etc).
Does NOT work on AUTO at all
How does display show heat? I set the temp dial to whatever (low or high) and turn the fan on manually or in auto mode-- no heat at all.
Not a mechanic so will need to have my mech look at it on Wednesday. I will check ALL the fuses just in case but as I said the cig lighter works really well.
BTW, my car only as about 81K miles......

O. L. T.

iTrader: (17)

Don't care if your cig lighter works or not, never said a word about it. You can fix it, or we as a forum can help. Don't out think us on it. You're going to have to follow through on each check without avoiding anything because of checking something else at another time or following through on something unrelated you read elsewhere. If you don't do it exactly as read, you'll be paying a mechanic.

Once you've verified all the fuses properly with a continuity check via DMM, you are going to have to do the following based on what you want to do from a wallet standpoint of view.......

- Manually set the heater control valve to open and use your fan on manual setting. This will allow you heat, and full fan speed control. Provided you don't use the auto function, you'll never notice an issue and you've spent nothing.

- You will likely need to replace the climate unit brain since it is not the blower motor resistor, as it works on manual, and it is nmot telling the heater control valve to open. TWO problems that are unrelated by any means except the brain point to the main unit as faulty. Buy a used unit from the classifieds on here and save bunches of money, remove and install it with THESE instructions.

Good luck!

xspsi6

iTrader: (31)

What year is the car? I believe 97+ have no ecu or blower motor resistor for just the climate control however I may not have my facts 100% straight maybe OLT can chime in on this ?

petersc400

O.L.T.-- Thanks again.... and I appreciate your concern for my wallet! I'm thinking I'm going to go ahead and look for a good used climate control brain as the car is perfect otherwise. I'll let you know how it all sorts out but your advice has been GOLD! That's what I love about this club... so many members with good knowledge and WILLING to SHARE!

petersc400

O.L.T.-- forgot to ask. When shopping for climate control brains will all years (92-00) work or do I need to stay with the first generation (92-95)? I may have line on a '96 unit.....

O. L. T.

iTrader: (17)

I believe it is below 97 will work. The 92-93-and some 94 are black back and 95-96 are white back (just to distinguish the difference if looking at them and wondering).

Tell you what, pay the shipping to Cali and you can try my spare one to see if it works before you go buy one.

petersc400

Thanks fo the great offer, O.L.T.... it appears the problem is the solenoid in the heater control valve... the climate control is OK. So, I've sent for a new heater control valve online (about $275) that should arrive shortly. In the meantime we moved the hoses to bypass the auto system and i get some heat on manual. The new part should be installed later this week or next depending on my schedule. I'll let you know how it works....

BTW, your help was invaluable in the process and it's why I really enjoy this forum and club. For a non mech I'm learning a lot about these cars. Just picked up a CD of the owners service manual on ebay very inexpensively, too.

On a separate note, while scoping the engine we discovered that the mass air sensor was shot and not working (no warning light came on or anything) and must have been working in a limp mode or something. Fortunately, my mech used to have a lexus v8 and had a used MAS in his shop that he had purchased for his future use (given how many $$'s they cost) and let me have it very cheap as well as cleaning it before putting it into the car. I didn't realize how subtle the performance had degraded until he put it in... car is very sweet right now!