Hi,
I read some of the threads here and it led me to believe the servo by the bellowing fan is faulty. I removed it, opened it, cleaned and applied silicone grease and placed it back, but the noise is still heard after a week of driving and no hot air. I have noticed the noise goes away when the air recycle button is off. it makes a noise when it is ON only. It could be that what I have done did not fix the problem on the servo or it is something else completely. Does anyone know?
Thanks.

 

Hello,

A video of the sound would be helpful.

Here is a thread on how to diagnose no heat in one of those cars, try entering the Diagnostics mode to see what codes you will get. The Recirculation servo is located just above the blower motor under the glove box, the first thing to do would be to check the interior air cleaner located on top of the blower motor, below is the video on how to access it, failure to service one in time is the most common cause of the strange noises and erroneous smells coming from the HVAC unit in the car.


Besides that, there isn't much to tell without actually hearing the noise in question.

Hope this helps and best of luck!

 

Arsenii thanks for replying. While I was repairing the servo, the one to the left of the blower, I checked the filter and the area. The filter was replaced in my last service and looks like new. The noise, I have to try to record it in a garage since it is very low, (like the servo is hunting its position). However, the servo I cleaned, based on that video, it depends on the temperature setting, but the noise is there when the AC and all are off except the recycle button illuminated green. With AC off, by toggling the recycle button I can stop or start the clicking noise. I assume it has to do with the gate or such, but have no idea where the gate located is being controlled by the recycle button. It is a low random clicking noise (no predictable frequency) like if you were scratching on a table with two of your nails. However, I should try to record the sound later.
For cleaning (around 3:00)

https://www.youtube.com/watch?v=KeU2uZ5tJFQ&ab_channel=LahisTech

The servo I cleaned

You Tube

 

The servo you cleaned is for the blend door, the one responsible for the temperature, to the income air. If cleaning it didn't solve the issue with heat being different on both sides, you will have to follow the steps linked above for more in-depth diagnostics.

Here is a Parts Catalogue for your car (marked 87106N), the Income Air door and its servo are located on the blower motor under the Passenger glove box, right above the air filter closer to the door. You can take the glove box completely out, turn the blower motor Off and Recirculation On, listening for the noise in question. If it is present, try disconnecting the servo, that is if you can reach it, and see if the noise will stop with the blower motor both On and Off, that will indicate that it is the servo at fault. If the noise stays with the Blower Motor On, there may be an issue with the door itself or something getting stuck in the unit.

Those servos had an issue with the potentiometer that gives a feedback in its relative position, the traces would start wearing out, causing servo to start moving until the signal is back again, and then attempt to move back to the desired position, only to reach the dead zone again, this cycle is called Servo Hunting. If cleaning it doesn't help, you will have to get a replacement from junkyard or eBay.

Hope this helps and best of luck!

 

Hi Arsenii,
I performed the self test per the thread. First try, I saw 21, 24, 41. Then went through the PDF file to see what they are. 21 with *2 on the file perhaps relate to the two On and Off of the light sensor, and that I did not see 24 on the file. So, I went back and placed a light over the light sensor and ran the self test. This time I see codes 21 and 41. So , I assume the 21 is always going to be reported since it indicates the status of the sensor in dark or in light, but 41 seems to refer to the servo I had removed and cleaned up nicely. What do you suggest?
Thanks.

 

Which servo did you remove, the one on the Driver or Passenger side?

Code 41 refers to the Damper servo motor circuit on the Passenger side, according to this code, it is the Passenger side that will have issues adjusting the temperature. Try disconnecting the battery for a few minutes to reset the codes, and then watching Servos move as you adjust the temperature on both sides to see which one will not spin in the process, that will tell which motor is not working, and which code was caused by the servo being disconnected instead of an actual fault.

Codes 21 and 24 refer to the Light Sensor in the dashboard for Driver and Passenger side, the trick is that they are both connected to one sensor in those cars. This code will always pop up in dark environments, and it is safe to disregard for now. If you want to get rid of it for now, place a flashlight on the sensor when you disconnect the battery, and leave it there for the time being.

Hope this helps and best of luck!

 

I removed, disassembled and cleaned the passenger side servo, the one to the left of the blower.
Could you clear up this line from your reply for me. I can't relate? "and which code was caused by the servo being disconnected instead of an actual fault."
Also, will I lose all my radio station settings if the battery is disconnected?
Thanks

 

What I meant is the fact that you likely disconnected the servo while the battery was still plugged in, which likely caused the Climate Control Unit to trigger the Circuit fault code, since it was unable to locate a servo. With the code stored in the memory, the Climate Control will run in fault mode, likely avoiding using that servo altogether.

To make sure that the code you have stored in the system is indicative of an actual fault, and not a leftover code from the time when the servo was disconnected, you need to reset the codes and then enter the Diagnostics mode again to see if the code will return, that way you will know for a fact that there is indeed a fault with that servo.

True, I haven't thought of that.. Instead, you can pull the ECU-B fuse, here is a diagram for your car, that shouldn't affect the radio.

Hope this helps and best of luck!

 

Thanks for clarifying, now it makes sense to me. I pulled the EU-B fuse (#1 location) from where I had no idea it was a location for the fuse box, I thought it was a coin box only. However, I ran the self test with a flashlight placed over the light sensor. Now, it shows 00 and 24. I have to test drive it later as it is too late.

 

Hi Arsenii,
Please see the last email first. I drove the car during the day to get the water hot and redo the self test. I noticed the noise I was hearing near the passenger side by the dash is gone. So apparently cleaning up the servo relating to code 41 was good enough. I ran the self test, it returns code 00 only. However, I still do not have hot air, even as high as 85, I get maybe 75ish bellowing down to the legroom area. Could it be that the heater core is blocked or is it something else? I am not sure if in this model the bleeding is an issue as it used to be but I never remove any fluid more than the amount needed to add the FiberLuck. Couple years ago, I used one time serving of FiberLuck for a very small leak, Could that have blocked the heater core? Note: the temp gauge shows the same reading as it did before I used the Fiberluck.

 

Code 00 indicates that the system has no faults and is functioning normally.

I would say I am really not a fan of any radiator stop leak stuff, something that stops leaks is deemed to create clogs in the system. Heater cores in relatively modern cars tend to have very narrow passages to maximize efficiency, which may be your problem, below is a video of a heater core cutaway showing the lines that the fluid circulates through.


What you can do is try taking the lines coming to it off, and doing the procedure described below, not to necessarily flush it, but rather to see what kind of fluid will come out, and how good of a flow you will get through the heater. If the flow coming out of it will be quite restricted, knowing that it likely has stop leak trapped in it, it may be easier to replace the unit instead of trying to salvage it, fortunately, as far as I know, you don't have to take the dash off to access it.


Hope this helps and best of luck!

 

Hi Arsenii,
Thanks for good videos and I have seen a few other ones, but not for my car. The inlet and outlet hoses are hard to access. Their position on the firewall lined up with the position of the radio button inside the car, almost 2 ft away from the driver side with a tight opening smaller than an arm to go through. They also have spring hose clamps with hard positioning to align a tool if one can find a 24 inch needle nose. I have to add, the radiator fluid was replaced per preventive maintenance by the Lexus dealer as it is very clear and new. However, in your video, it refers to a control valve that allows the radiator fluid to run into the heater core, is there such a device for this model or does the fluid run continuously?

 

ARES Flexible Hose Clamp Pliers

ARES Flexible Hose Clamp Pliers

The main radiator has a drain plug on the bottom, drain the coolant in a clean sealable container, make the repairs needed, and fill it back into the system, though you will still need some new coolant to offset what will remain in a heater core.

One was present in the older models, but not anymore. To be safe though, turn the heat all the way to Max Hot on both sides and disconnect the battery, that way you will ensure that even if there are any valves in the system, they will stay open for the repair.

Hope this helps and best of luck!

 

Thanks for the link for the tool, but I have to find a way to open up the access space a bit since it is very tight to reach, especially this tool needs to be engaged by hand onto the clamp that needs to be turned a bit for alignment. The reason I was asking for the in line valve was to avoid all the draining just in case the valve itself is the failed device. Is there a diagram showing if there is a valve indeed? However, I appreciate and understand your suggestion and procedure.

 

If it were to be present, it would be shown here, just like in this diagram for my 2000 ES300.

Hope this helps and best of luck!