mlgbwk

greetings..

When I turn on/off the AC, OR, adjust temp from low to high or vice versa, the loud noise comes and lasts about 5-10 seconds then gone. It is not a chirping or gerbil or any kind of sharp noise, it is more like the motor has trouble start/stop or you put a card in bike spoke.

So is it more like servo or AC blower motor? Is it a DIY-able job? btw the AC does blow cold and hot air, but not so much below 3 bars (I had a es300 and I did not realize rx300 has like 8 bars max, so I assume I should not expect much air below 4 bars).

Thanks in adv!

salimshah

Try changing the MODE settings and see if the problem shows up. If so it is your mode servo. There is plenty of discussion on servos.

Salim

carguy07

I have never heard a servo make a bike spoke sound. I would take a look at the blower motor. Could even just be some leaves or something in there.

mlgbwk

hi, i just tried and it seems changing mode does not trigger it, only adjusting temp or turn on/off the AC. thanks.

QUOTE=salimshah;8213934]Try changing the MODE settings and see if the problem shows up. If so it is your mode servo. There is plenty of discussion on servos.

Salim[/QUOTE]

mlgbwk

Thanks! Is the blower motor behind glove box and can be visually examined if I remove the glove box? Or it is something that i have to ask a professional to check...

carguy07

The blower motor would have to be removed to check it, but it looks pretty straight forward. I would pull the glove box. That way you can see the servos to confirm that they are working. It looks like the blower motor just pulls out from the bottom behind the glove box. PM me an email address and I can send you a PDF that will help you take it apart.

carguy07

Here's a good thread with pics of the servos: https://www.clublexus.com/forums/rx-...old-air-4.html

Glove box comes out with 2 screws up top, 2 small bolts down low, and give it a tug toward you, there are a few metal clips up at the top that you have pull it out of.

salimshah

I would still suggest a few easy things first, before diving headlong into blower motor repair.

Remove the cabin filter and check.

Try adjusting the fan speed to confirm it is related to fan motor.

Last remove the glove box and see if you can trace the source of the sound.

There is a mix servo which can be noisy and that is controlled by temp setting.

Fan motor can go bad, but clogged filter and the servos are more probable to fail/act-up.

Salim

mlgbwk

Actually you are right! I did not yet remove the glove box but I am now pretty sure it is the "Mode" servo motor instead of the blower motor which I suspected before.The noise source sounds more close to radio control panel area than the glove box though.

I don't know why it did not happen at 1st day but now obviously changing AC mode will 100% trigger the grinding noise, and changing AC speed level does not really trigger it. Turn on/off is 100% trigger but I guess the mode servo motor is involved then so it makes sense.

btw Where is the filter located and how can I check it is clogged ?

so my plan is to follow this link https://www.clublexus.com/forums/rx-f...old-air-4.html and buy the part for $150 and replace it, but can you explain what you mean by "UNHOOK NOT UNPLUG" the yellow SRS cable? It sounds a bit scary as I know it is not funny if the airbag blows..

Thanks!

carguy07

When you pull the glove box, there is a yellow srs wire and connector that is attached to the back for the box to keep it from flopping around, just remove the connector from the box, but do take the connector apart. IE wire will still be in tact, just not tethered to the glove box.

The filter can be accessed by removing a little panel that is inside the glove box, behind that is a rectangular plug that you pull out and the filter is there.

I just replaced my mode servo, it is very easy. Paid about $115 to a dealer on ebay. I found that an obstruction screwdriver like this made the job go quick.