Air Conditioning Problem Ls400

[Jason 92 Mk1 LS400]

Hi all,

I've owed my 92 LS400 for 2 months now and found this site whilst searching on the net tracking down the problems with my LS400 - wish I had found it sooner! - Many of the posts have been very interesting reading - its seems I am not the only one with problems, (my power steering pump is being replaced as I speak (or type!).

Anyway, I bough my car "very cheap" (I am not a rich bloke!), I knew it would need some work doing to it - How much I didn't really know.

(New timing belts, new wheels (not just tyres, the wheels), Steering pump) Loads of body work - You ever tried to match pearl white paint - What a ..............etc etc and now the Air-con

I knew the aircon did not work when I bought it, being an optimist I thought a gas re-charge would sort the problem out (STOP LAUGHING !). The air-con guy who came to recharge it says the compressor is at fault and needs replacing (this is after he took 85 notes for a re-charge !). He as quoted me approx. £800 to replace the compressor and re-charge, however, he won't guarantee that this will fix the problem.

I can just about swallow the £800 it would cost (Please tell me if this is too much), but for this amount I want a guarantee - As anybody else had this same problem ?, is it a common problem ?

Any help or comments would be appreciated.

Ps Ignoring the problems, which you may say I asked for buying a "cheap" Lexus, the car is great, it has done 116,000 miles but drives very sweet (except for the wheel wobble which will go when I get some new wheels - I would like those off the SC430 - nice 18" - but these probably cost a fortune !).

A bit of advice from me - If you are considering an old LS400 - don't buy the cheapest, get the best you can afford and make sure all the toys works. When you test drive it, get it on the motorway - I only found out about the wheel wobble on my way home after I had handed over my cash.

:iraqi-info-minister:

[Jim Walker]

Well Jason, welcome to our world. These are great cars and rarely fail, but when they do, you had better be prepared with a fat wallet. When the dealer gets done with you, that wallet won't be thinner, it'll be GONE!

I can't help you with this problem, but I can with a potential future problem. You see, the 90-94 LS400s are notorious for the failure of the TEMP / TIME Climate Control LCD. They will begin to fail by showing a smudged black display. It will usually clear up on hot days, but the smudged black look will return when the display cools down. This will continue to worsen until it will always show the black smudged look no matter how hot it gets.

The Lexus dealer wants approximately a ton of money to repair this problem. They replace the whole climate control unit itself. This unit has lots of electronics in it including the climate control computer itself.

I am an electronics engineer so I decided to explore this problem and I found that the glass liquid crystal display itself is the part that fails, as opposed to an electronic component that drives the display. These displays are custom made for or by Lexus so you can't just go to the neighborhood Liquid Crystal Display store and by a replacement. Lexus won't sell them, they only sell the whole climate control unit.

I decided to have some of these manufactured to my specifications. I ordered these with the widest temperature range that I could possibly order. Since these are custom made, it will take a while to get them and they are expensive but not nearly as expensive as going to Lexus.

Anyway, I am expecting delivery of 5 engineering samples within the next few weeks. Once those are tested by me and I determine that they are acceptable, I will order at least 100 of them and offer them for sale to this forum at a very reasonable price.

I have found the there is a difference in the displays between then left hand drive cars as opposed to the right hand drive cars. The ones I'm having manufactured are for left hand drive. It will require an adapter to use these on right hand drive cars. A daughter-board that will allow the use of the same display to be used on right-hand drives. I will design and offer these as well.

Anyway, if you or anyone else out there is interested, please Email me and let me know.

Jim Walker jimlwalker@sbcglobal.net

[obergc]

Jason,

I too bought a fairly high milage 93 LS400 and I am having fun clearing up the problems one by one. My air conditioner failed on the drive home after purchase, about 3 hours into the trip and I too hoped that a recharge would cure the problem. No such luck, my problem first showed up as a blinking a/c light on the climate control console, later found out this was a sign that the a/c compressor was locked up. Sure enough, when I got home and checked under the hood, the a/c compressor clutch would engage but the compressor did not rotate, got a momentary screech from the serpentine belt when it tried to drive the frozen compressor and then the a/c system disengaged the compressor clutch. My 93 Lexus a/c system used R134a gas and I believe that your 92 will use R12 gas which complicates the repair. I found a rebuilt compressor from these folks http://www.auto-air-compressor.com for $299 and I must say that the guys at Pace Compressors in Tampa, Fl were very pleasant to work with. They specialize on rebuilding the NipponDenso compressors that are used on many of the Asian autos. The folks at Pace said that usually when a compressor fails, it shreds itself and pumps the a/c system full of metal filings. The beauty of the Lexus a/c system is that it has a frozen compressor sensor and it shuts the compressor off instead of allowing it to shred itself. I replaced the compressor as well as the condensor and expansion valve but I did NOT find any filings anywhere inside of any of the a/c system components, they were all surgically clean. Not sure if you can even purchase R12 gas anywhere and I have heard of some horror stories regarding converting R12 systems to R134a but that my be your only option. BTW, the guys at Pace have developed a servicable a/c filter that you can install in the suction line of your system to filter out any metal filings that may remain after you purge the system. They sell the filter very cheap for $25 dollars and a replacement filter element is only $2. The filter protects the replacement compressor from damage that will occur if metal filings are ingested by the compressor that will be circulated with the gas and oil. I don't know if Pace will ship internationally but if they do, I highly recommend them. First thing I did when I purchased my Lexus was to buy the two book set of Lexus Shop Manuals, they have detailed information on how do do most everything on the car and I feel that they were well worth the $144 that they cost. You can buy manuals on a CD much cheaper on eBay also but I do not know if they are the same as the Lexus manuals. I replaced all of the a/c components myself (compressor, receiver/drier, condenser, and expansion valve, all of which Pace shipped to me for a total cost of $835, delivered to my home in Fort Walton Beach, Fl. While I think I could have gotten by by replacing just the compressor and installing one of their filters, I basically have a new a/c system for under $1000 and it is pumping COLD air once again. Good luck in getting your a/c fixed.

Curt

[Steve]

Welcome to the club Jason

Where are you in the country?

sound slike alot of things need doing.. my Import has done 116,000 and runs like a dream...

the only problems i am getting are the power windows need replacing and a few bushes and shocks which i have already replaced....

when you say the wheel wobbles is this at a certain speed?

[obergc]

For Jim Walker,

Jim, I believe that by now, there are few NEW problems that are surfacing with the 90-94 LS400s and I applaud your efforts to repair the electronic components at the most economical cost. I also do not appreciate the need to replace an expensive electronic unit that can be repaired by replacing a failed component. I do not have a bad LCD display on my climate control yet but I have had some problems with LCD displays that were damaged by exposure to the sun. I believe that it is reasonable to assume that down the road that I will probably have the same problems that you have found and I would be very interested in acquiring one of the LCD displays that you are talking about. I plan of keeping this 93 LS400 for the long haul and I want to keep everything in working order. Please let me know how much the LCD display will cost. Now that I have my a/c working, I will next tackle the problem of the intermittent operation of my tach and speedometer needles, I will probably be talking to you about this also.

Curt

[Jason 92 Mk1 LS400]

Jim, thanks for this - yes my LCD has the black smudge, which disapears when it occasionally gets warm. If I manage to get the air con working, I am interested in replacing the LCD (depending on how much £££) - If I can't get the aircon going, I dont think I will be forking out cash on a temperature gauge that tells me how cold my car isn't - I think I would rather not know when I am driving down the road with all 4 windows open and the sunroof trying to keep cool B)

Curt - again thanks for your reply, it a shame I dont live in the States, sounds like you have the problem sorted over there. You are right about the coolant, mine is the R12 gas, but the guy who did the recharge filled it with R134a (I think I have these the right way around ?) gas saying this would be fine and it is a "standard conversion" - any comments on this as to if it is true would be appreciated. Oh yes I have the blinking light

Admin - thanks for the welcome, I am near Manchester and yes, I do have many problems to sort out. At the moment I am thinking of "cutting my loses" - although I still love the car, I think I should have bought a better example.

The wheel wobble starts at about 60Mph, which is most anoying as I do quite a lot of motorway miles - It is really bad between 75-95mph (my usual cruising speed) but over 110 it goes (but so will my licence !)

I know its the wheels, they are not the originals and when I took em to be balanced, I saw on the machine 3 of the wheels were not running straight and Mr quickfit did not charge me anything but did say "Go buy some new wheels"

[Matthew_McNally]

Jim, thanks for this - yes my LCD has the black smudge, which disapears when it occasionally gets warm.

Jason

this post details replacing burnt out needles on Lexus LS models dashboard

;)

[obergc]

Jason,

From the research I have done you cannot just charge a R12 a/c system with R134A gas, for one thing the R12 system uses a mineral oil for compressor lubricant which is cycled with the gas and the R134a system uses a synthetic PAK oil and I hear the two oils are NOT compatible. I would contact the folks at Pace Compressors to see if they would ship international for you, shipping charges shouldn't be toooooo bad. If I had to do my repair over again I would just install a rebuilt compressor, a new receiver/drier and I would install a filter in the suction line. Total cost of parts should be approximately $375 plus shipping. Total parts needed is compressor ($299) + receiver/drier ($26), filter ($25) and one can of PAK oil ($8). For a conversion, I would also remove the condenser and have it flushed to get all the R12 oil out of it. After replacing these parts, install the filter in the suction line and I can send you instructions and a picture of my filter installation, run the system for about 1/2 hour and then replace the filter element. Rechage the system with R134 and you should be good to go. I will warn you that removal of the condensor requires removing the front bumper which is a bit intimidating at first which actually wasn't too bad with the information in the Lexus shop manual. Good luck Jason and don't give up too soon, this is a great car and mine is shaping up fast. I realized that I was going to have to put some money in the car but I was fortunate in that the previous owner had just put a new power steering pump and alternator and just replaced the brake pads.

Curt

[Jason 92 Mk1 LS400]

Cheers Matt - interesting but my needles are fine (is this another problem on its way ?). My black smudge is on the Radio LCD display and a little bit on the temperature display.

[Jason 92 Mk1 LS400]

Curt - i was told by the Aircon guy that it was illegal to use the R134 gas (The orginal in the system) and whever I went for this, nobody would touch it - hence the R12 going in.

The parts in the US seem very cheap - just for the Aircon compressor I have been qouted £650 ($1000 aprrox) just for the part.

If nothing else, I am going to shop around for the parts and I think perhaps consult another Aircon specialist for confirmation on the type of gas

Cheers !!

[flotsam]

"however, he won't guarantee that this will fix the problem."

"I only found out about the wheel wobble on my way home after I had handed over my cash"

Yes! We've all encountered this problem. It's called being ripped off!

On a potentially more helpful note I read somewhere that the Soarer air condition has diagnostics. On this model you hold down the a/c off and airflow direction buttons when you turn the ignition on. Haven't tried it myself yet. Keep forgetting to.

[Jason 92 Mk1 LS400]

I am getting my R12 & R134A mixed up -

It has originally R12 gas (which is now illegal) - So Mr AirCon filled up with R134A.

I have found an interesting web site that explains the whole system, and how to convert from R12 to R134A (which the guy who filled up my aircon did not do - watch out for this Pre 1994 LS400 owners)

http://www.powerbase-auto.co.uk/retro-fit.htm

Pity they are 250 miles away - umm but if I get stuck it may be worth the trip.

Anybody in Kent who can put up a poor LS400 owner for a night or two whilst I get my aircon fixed !!!

[james2210]

Check under the bonnet for a sticker which should say what type of refrigerant your system takes. On my GS300, there is also a sticker on the bonnet lid behind the radiator grill that says what type of compressor is fitted and how much refrigerant and oil it takes. As flotsam mentioned, you should be able to do a diagnostic on the air-con system. On mine, you hold down the AUTO and the button that changes the air from outside to recirculated while turning on the ignition. Error codes should then flash up on the display. If there is more than one error, they are shown one after another. There is an excellent and really helpful (but unfortunately in the US) website AIRCONDITION.COM that might be able to give you some more pointers.

Good luck, and keep an eye on your wallet

[TURNER]

Hi Jason

Welcome to the club about time we had a few more LS400's to compete against them IS 200 owners

Also thanks for all the info about the air con believe it or not the company is only 10 miles away from me and i never knew it was there but do know

Also there are a couple of travel lodges around that area not that far away and some cheap B&B's

i only have a small flat mate bit cramped with all of us in it a the moment

hope you get sorted

cheers

Andy

[Jason 92 Mk1 LS400]

James - cheers for the tip - I found the label my system is R12 and I think the compressor is SAE J-639 manufactured by Nippondenso Ltd (Japan!!) - if anybody knows different, please let me know.

I have sent the details off to the aircon people in kent who are letting me have a price for the conversion to R134A and replace compressor/ seals / receiver etc..

I tried the diagnostic - I spent over an hour pressing various combinations of buttons but nothing

Andy - it looks like I will be visiting that travel lodge near you very soon :)

[Jason 92 Mk1 LS400]

I have managed to do the diagnostic on the air-con (After spending a further hour messing with it in Adsa'a car park whilst waiting for the wife) . It is showing diagnostic codes 21 then 33 - anybody know what these mean ?

[Steve]

if you are willing to travel and get a decent job then i recommend Auto Air in Poole, Dorset

http://www.ac4car.co.uk/

These guys are brilliant and the proprietor is a really friendly and honest guy! These guys also fit systems into cars that were not manufactured with AC.

My motor still takes the R12 but there is a replacement gas now.. you do not need to convert your system and i have been using this replacement gas for 3 years and works a treat! Mine is so cold it nearly gets frosty!

[james2210]

Don't know 10000% whether these are the meanings of the codes you have given. Try calling a helpfull Lexus dealer and see if they'll look it up in their Lexus bible if you ask them really nicely.

I think

21=Solar Sensor

This is a little sensor (you probably have two) on top the dashboard that are used for the automatic headlights and also to see if it's sunny. The warning can appear if the sensors are in the shade.

33=Air outlet damper position sensor

Tells the AC controls which outlets the air is blowing from.

Bear in mind that either of these codes could be set because of a fault in the AC controls itself.

Good luck. Looking at the weather forecast for the next week, I'd make sure the wipers work rather than the aircon!

[SKIPPY]

I HAVE A LS 400 AND HAD THE ORIGINAL GAS REMOVED AND REPLACED WITH THE CURRENT SPEC GAS AND IT WORKS JUST FINE HOWEVER I HAVE A WHIRRING NOISE WHEN I SWITCH ON MY AIRCON WHICH CHANGES TONE AS IACCELERATE DOES ANY BODY ELSE HAVE THIS NOISE MINE IS A 93

[jsweb]

Hello,

Ran across this board while searching for A/C issues with my 1992 LS400. Sounds like I'm not alone! The LCD was out when I got it 25,000 miles ago. Two weeks later, the A/C went out. The shop ran leak tests, said it was good, recharged it, and sent me on my way. Two weeks later, the A/C was gone again. This time, there were massive leaks. Interesting...

Spent $1500 to replace the compressor and recharge, only to find out that the evaporator was leaking as well. $1200 more out the window. I wouldn't have paid this much, but I was already $1500 into it, so I didn't want to blow it for nothing! Now, two weeks or so later, the A/C is still blowing sort of cold, but not as cold as it seems like it should. Does anybody know what temperature is normal for it to blow? It seems to take fifteen or twenty minutes to cool down the car now. I've replaced the major parts, and it's still blowing colder than no A/C, but I have no idea what else could be wrong!

Then, today, my climate control "auto" switch (which worked well before), now turns the fan to low automatically. The fan will work on Hi, but when switched to Auto it shuts to low no matter what temperature the car is. Any ideas?

Meanwhile, in the time I've owned it, I've had a rear main seal go out ($500), the passenger's side door lock go out ($400), the master window switch go out ($400), the brakes have begun to squeak, and there is a slight shimmy when driving freeway speeds. I notice that I have SC-400 wheels. After reading some of these posts, I think I see why.

For a car that was "in perfect condition" according to my pre-purchase inspection, this car has just been a money pit. My past experiences with older Toyotas has been excellent, so I figured this would be no different. WRONG! To be fair, though, it does have 175,000 miles and runs smooth (for now).

Thanks for any suggestions and feelings of empathy!

Johann

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