BlakeRX300

So my issue on my 2001 RX300 was air would only blow from the floor and when i went to blow it from the dashboard vents it made a annoying loud noise. I used this forum to troubleshoot that it was the mode servo. I took that thing apart and cleaned it using the instructions provided by some of the members on this forum. However, when i put it back on the vehicle I still had the same issue. So what i did to actually fix it was move the spring that is circled in red out of that notch, which allowed my mode servo to be able to move those arms in the position you see in the picture to allow air to flow through dashboard vents. My worry is is this an acceptable way to fix the issue? If so I just want to let others know of a way I had not read about others doing. By the way if I have the spring the way it is designed the arms would lock up in this "-" position. So the motor couldn't generate enough force to move them down to what is shown in this picture.

lovemy99rx

Hi. My 99 rx will only blow from the vents, and I've been scouring these forums for hours looking for a fix that I think I will be capable of doing - this will be my biggest DIY to date.... I already had the glove box off and was right where you are in the picture, but hadn't done enough research to attempt a fix at that time. So I put it back together and started reading. I plan on working on this tomorrow, at the very least, take out the mode servo and clean it up to see if that will allow it to switch modes, but your fix looks so much easier! I know that this post is almost a year old, but if you or anyone else knows if this is a BAD way to fix it, could you please let me know? Otherwise, I think it's worth a shot If you know that it DOES work for the long haul, please let me know that, too!! I have a number of things that I have to fix on my car and the cost is skyrocketing. So I'm going to try some of these DIYs, maybe I can get a little help from a mechanically inclined buddy. Wish me luck! And thanks for the post and picture!!

lovemy99rx

This is my first time posting, so I'm afraid I messed up and duplicated my replies Anyway, I just wanted to say that I'm going to try this tomorrow and since there are no other replies on this thread, I hope that no problems arose from doing it this way. If anyone knows differently or has more information, I'd appreciate it! Thanks much!! These forums are wonderful and I've already learned so much, which is a good thing since I have a lot to fix on my car and not a lot of money to spend. Hopefully my first DIY will be a success

salimshah

The purpose of the spring is to provide detents (steps) in position of the lever settings. Remember the old times when the levers were moved by hand and they would stop at each position. These stops would cleanly open and close the desired ducts.

As the motor weakens it lacks the force to overcome the spring resistance.

Without the spring, you will get slop in the lever position (partial or leaking duct-doors). Eventually the motor will totally fail.

If you plan to keep the RX, part with the money to buy the servo and get your moneys worth by using it.

Salim

lovemy99rx

Salim, thank you for your quick response! I have found quite a number of threads concerning taking the servo out and cleaning it. It seems to work sometimes, though it may not be a permanent fix. Being strapped for cash I think taking it out (which I know I can do) and cleaning it by following the instructions laid out on another thread, I at least have a chance of freeing it up so that it will be able to switch modes again - if even for a short time. I'm sure that I'll eventually have to invest in a new one, maybe sooner than later, but this may solve my problem until I have enough saved up to buy the new parts I need.

This is my third rx300 and I've only had it for a week. Unfortunately, the previous owner did not take very good care of this beautiful car and so I have to prioritize the things that need to be fixed. I have spent hours searching the forums today and have found so much wonderful information! I'm going to try to do as much as I can myself, and I'm planning on working in my dad's garage, so I'll have access to more experienced people if I need help

I appreciate your advice, and the more I think about it, the less I want to mess with the spring

I'm sure that I'll be spending a lot of time searching these forums, but I also know my limitations and will only attempt the fixes I think I'm capable of. I have to have all of the fluids checked/changed ASAP, but I'll be going to a mechanic for that! I also have need to replace the front door actuators and that scares me to death!

So, one thing at a time. But let me say that you guys are a great group and will be a wonderful resource for me in bringing this car back to life

Thanks for all of your help! When I do this, I'll post back if the mode servo works after cleaning
Sue

lovemy99rx

And worst case, as long as I don't break anything (and I will be very careful!), it does still blow heat and a/c through the dash vents, and it doesn't make noise or anything. So I could just put it back in and live with the air in my face until I can get a new one

thanks again!!

salimshah

Least invasive is to help the system get in the mode you want and then let it stay there (dont set the climate control to auto).

If you are facing multiple projects, prioritize them.

Salim

powerslide

I did the same thing 2 years ago and removed the spring. Had cleaned the motor contacts twice. Still didn`t help. I ordered a new servo assembly and it was fixed.

lovemy99rx

Powerslide,
Thanks for posting!! The mode servo isn't my top priority, but I know that it is giving me good practice at DIY and I'm learning a great deal about my car Your experience isn't encouraging as far as going this route, so I'll probably end up ordering a new servo and installing it down the road, but at least by then, I'll be a pro at getting to it and getting it off!! I'll try to clean it because I know for a fact that the previous owners were terrible at maintenance (I've been cleaning and cleaning!!), so it's worth a shot. But even if that doesn't free up the modes, I still have air blowing through the dash vents.

I'm getting a bit paranoid seeing all of the things that this guy just let go so I think the first thing I need to do is take my car to a mechanic and have all of the fluids checked, and some probably drained and changed. I'm particularly worried about my trans fluid. My last rx needed a new trans, and I don't want to go through that again So I need to make sure the system is in good shape!

The trans fluid doesn't look filthy, but I'm not willing to trust my own judgement on that. Once that's taken care of, I can play with the servo and an oxygen sensor that might be bad. (I need front door actuators, but that looks like a huge job for me, so it will have to wait.) There is so much great info on these forums and such helpful people that I already know what I'm looking for and where

Would you happen to know if I should be concerned with any other fluids besides the transmission and getting a regular maintenance oil change? My car has almost 128k and I have no records of what has or hasn't been done I've changed the cabin and engine air filters and wiper blades (and cleaned ), but I've only had the car for one week Everything is running smoothly, no noises or error codes, but I want this car to last!!

Thanks for your input and your help!! I really appreciate it!
Sue

powerslide

I cleaned the other servos and they did good. Just the heater flap one has more pull on it. Make sure you test them and get the right one that`s making the noise. Replace your PVC valve and clean the MAF sensor. Look at my post towards the top for 2001 rx engine miss from dead stop. Rep trans oil and filter. Do not have it flushed. Use a good syn. trans oil. Look at the sticky info.`s. for oil type you want. Get a good one. Gonna have to pay more. I don`t change mine that often. About every 25,000 miles. It`s up to you. There is a design problem when the earlier transmissions and you can change it once a week and it won`t save you. Just keep the oil clean. You have no record so change it. If you have AWD then you have to also rep. transfer case oil.

lovemy99rx

Powerslide,
Thanks so much for the information! Definitely what I needed to know. I've had a lot of advice this week about the trans fluid and that flushing, etc. is a bad idea. I'm going to a mechanic I know tomorrow to get an oil change and I'll make a list of all of this info so that he can do this for me. Good to know about the transfer case oil. Then once I've done all that I can with that, I can work on starting my DIY fixes!! I'll definitely check out the sticky info. There's a lot of great stuff there I can't wait to get started - maybe I'm crazy
I appreciate your help once again!
Thanks!!

BlakeRX300

First off, big thanks to salimshah for sharing that great piece of knowledge on what that part I removed does. I have had that part removed since that post date and have not had any issues thus far, but it seems its only a matter of time b4 it completely fails. Not sure how long b4 the servo quits, but living in Texas I just hope it doesn't happen to quit here in the summer.

supranyc

I just finished this DIY today and it seems to have fixed my issues. salimshah - thanks for all the great info.

To the OP and other posters with this problem - did you guys just clean the contacts? There is some info regarding the worm gear - for some people this isnt an issue, but I believe its what fixed my problem. I had the 'clicky' sounds, but also had a really loud grinding type sound when i changed the MODE to anything but feet only. im convinced this was from the worm gear being disengaged. If you have this really load annoying sound, check into the worm gear fix.