Vudugan

Thanks, I still haven't got heat. I hate giving up but 3 weeKS has exhausted

Vudugan

It's me again, I got my heat back!! I shopped Craigslist for a local mechanic who I asked what he would charge me to come by and check this "no heat" situation out. He replied $30. He arrived and started with everything above right off the bat constantly checking the temp of the hoses at the HCV, that's when I felt he was legit. He then started pulling panels off from below glove compartment and that's when he was able to point out the servomotor area. He explained to me about the one "vent door"directly behind the radio just before engine compartment. This is what that HCV cable was associated with. He guess it might possibly be a leak in heater core but was not sure without opening up more of the paneling and making space to see. His assumption was based on Anti-freeze found on the HCV cable behind the paneling. However, I pointed out that the Anti-freeze was more likely to come from the HCV area where I noticed a very small slow leak from the screw in the corrosion of the pic above, he agreed since there was no other signs of Heater Core being damaged and no real puddles from leakage.
I paid him and thanked him for helping find this area I was afraid to venture into alone.

So anyway, here are some pics of what I found and did after he drove away. Hope they help anyone with their classic!

****No Tools required****
*****I am not a mechanic, just mechanically inclined.*****


Remove bottom panel under glove box


Remove vent section, there's only the tab in the 2nd pic that I pushed in and wiggled section free.




So this pic reveals the area of work, well the area to get into the area of work noted by the smaller circle to the left. I have to say, with out removing a lot of what you see directly in the pic, it makes it very hard to maneuver your way back to the small circle. A thicker person than myself may have a very tough time in here. Not to mention, I could only maneuver one hand, mainly fingers back there.



Looking in the big circle off to the right you will see a clip holding the HCV cable. This can be pulled towards you to release tension for cable setting it free. (My cable had a 90 degree angle bend in it with a loop identical to the end at HCV., I'm guessing it's a kink? and possibly the reason for popping free.


So looking in the big circle, to the left towards small circle, you will see the arms that I believe operates off the servomotor (this is how I got heat to work) (this was an incredible shot due to cellphone being able to get in a position for it. You will not be able to see this shot as clear physically/visually..)
1. Is pointing to the pin I came to the conclusion that it had fallen off of. I am unsure. Play with the temp control from HOT down, somewhere round 72 maybe, you will see the arm with this pin start to move towards you. Move it bit by bit until you can manually and simply push #2 away from you, passing the #1.


You should now have heat if nothing in this thread worked... Other than maybe a bad Heater Core.

BUT

If for any reason you drop the heat temp it will get stuck there, you will have to repeat this process which should only take 15mins depending on how agile you are to remove that panel under the glove box, removing vent, pushing the #2 arm towards driver side and buttoning up.

In conclusion, I purchased a 17 cent clip from hardware store and re-attached the cable AFTER straightening the cable out. This has resolved my heat loss. (Come to find out that a friend of mine has the same issue on his Ford Explorer and is using a route through the glovebox to activate his vent...)

[IMG][/IMG]


The link for post #4 below... Very Scary lol.

deanshark

Awesome heat is good. This system is weird and like I said before, very complex. It's crazy b/c if you open the heater valve by hand (taking off the cable) it still doesn't do anything. I guess it's b/c that cable still needs to move from that servomotor to move other parts in the system. It's also good that you were able to squeeze in there to get that to work. Or you would have to do this, post #4 https://www.clublexus.com/forums/ls4...d-removal.html
I'm happy for you that it wasn't the heater core. (like mine was) post #7 of this tells ya what would have needed to come out; https://www.clublexus.com/forums/ls4...ater-core.html

quantfutur

I have an '05 RX330 and having variable heat. Sometimes it heats well and sometimes runs cool air on 'high heat'.. Took it to a mechanic today who said it has a circulation problem - water not circulating and that it is either the thermostat, the water pump (he thinks less likely because pump was replaced 15k miles ago with timing belt), or a blocked heater core. I then called another mechanic who a friend recommended for a second opinion; sight unseen he thought he would need to flush the heater core. Also said could be that coolant is low in the radiator (I just filled up the coolant bottle, which was low). Said if the heater core is leaking, will be big $$$ to fix. But said 90% of the time, flushing the heater core resolves it. Neither mechanic thought it could be in the dash or the servo motor. Suggestions/comments? thanks

sardilou

The old fashioned method of removing air locks is to run the engine for the time required to achieve running temprature with the coolant expansion reservoir cap removed this allows any air to escape through the natural expansion and flow of the coolant without any pressure being created which in itself can create an air lock. Its worth a try and wont damage anything.

Yotarip

I don't know if the OP is still on this board, but THANKS SO MUCH!!!! This saved me hours of frustration. My 93 had this exact issue today and your post lead me right to the issue. Even my actuator cable was loose and bent to a 90 degree angle.

Vudugan

That's Awesome!! Happy to know this helped another, Stay Warm

drs23

Vudugan,

I'm experiencing the same problem with my wife's '97 LS400 that you just went through. I don't have the factory manual so I'm assuming your '93 would be the same as this one. I read this thread completely and started with the basics. I checked the coolant level and found it to be bone dry so I filled it to the FULL mark. I understand your heater valve would not open and this one (I just replaced) isn't either.

Before I brave the cold I have a few questions. The first is how is the lower trim piece removed? Is it screwed on, held with clips or attached in some other fashion? Second is did you ever determine if the cable was indeed bent and the actual cause of the problem. If so, how did you straighten it?

I hope these questions aren't annoying but it's dadgum cold out for SE Texas. I was out there for about 15 minutes adding coolant and burping the system and my fingers are already numb.

drs23

Am still attempting the heater repair on my wife's '97 LS400. I have removed this 'lower cover':



Does this upholstered panel need to be removed as well, and if so, how's it done?



I ask because what I'm seeing isn't like what Vudugan is presenting in his photos and I DON'T want to BREAK my wife's car!

I realize I'm a newb here but I'm desperately in need of help. Any feedback/answers are much appreciated.

cobalt91

drs23, due to changes in the model years the 93 and 97 are differrent. I dont have alot of experiance with the HVAC in these cars. Try a google search for a diagram. Or maybe sewell will have an exploded view of the mechanism. Hope this helps.

drs23

cobalt, Thanks so much for the reply. You are indeed correct. This '97 is nothing like his '93. Also this is air bag equipped so I'm sure that may be some of the difference as well.

I went ahead and removed the glove box per directions found here. Thanks billydpowe! Here's where I am now.

I "guess" I'm looking at the servo motor here:



I didn't find a kinked wire or cable going to it. The cable is fine but impossible to move. I guess this is why my heater valve on the firewall won't move.

Next question is how do I test this motor? I don't have a diagram to know where 'hot in' is or any idea what all the other wires in the connector controls. I did start the car and go from 72* to Max Hot and it didn't move on it's own. Didn't bring it all the way to driving temp, Does this make a difference? I guess my bottom line now is how do I determine it is indeed the servo motor before I start replacing parts *****-nilly. How do I bench test it?

I would really like to put this issue to bed so I can move on to why it's overheating occasionally.

Thanks again for the reply.

drs23

I found the purple wire going to the servo motor was the 'hot in'. I have power there. I hooked the servo motor to a 12v battery and it goes round and round.



Where would you guys suggest I go now and what to look for?

Thanks

Vudugan

I honestly hope someone will come to your rescue on this. As I mentioned in the OP I am by no means a mechanic and have no clue about the 97 Lexus . I had to get my 93 working the best I could due to finances. Only 6 degrees here in WI today and heat has been working as needed flawlessly since post. Best advice I can give until someone with more answers/suggestions come along is to Google and search YouTube for your symptoms as detailed as possible or request a mechanic as I did and tip him for any new useful info....

Wish you the best of luck!

drs23

That's cool Vud. I started a thread here. Not many responses yet. Prolly 'cause I'm a newb as far as posting goes but I joined in '09 so I have been here a while.

Thanks for following up on your thread. I'll get it done no matter what.

Great OP, though I'm learning that may be only one of my issues.

Thanks again.

jscoda

Had the same heater issue. The temp gauge on the dash was working. Thermostat seemed fine as hoses hot. Servo motor working fine. Cable not bent. Looked at the coolant reservoir and saw it was empty......hmmmm? Put a gallon of 50/50 coolant and heat started working again. Great thread and very helpful. Sometimes its just routine maintenance.