davidyal

I'm not the main driver of the car, so trying to recreate what happened. A few months ago, there was a loud noise from behind the dash (video below). Fast forward to this week, apparently no air is blowing at all. I feel cold from the vents, but no fan.

What is the way to troubleshoot? Does the previous noise indicate the motor may have died? or is there a control relay or fuse to check first?

Any advice appreciated

Lexmus

That sound can be the blower motor or the A/C mode servo. My mode servo made that noise only when the setting was on front vents. that vent position puts the most stress on the servo motor and it caused the servo motor to slip. If the noise doesnt change when you change the mode settings, either the mode servo is dead, or it is the blower motor.

To check the blower motor:
First, have you ever checked/changed your cabin air filter? the motor sits just below the filter and both are behind the glove box. Make sure you have a filter and that there isn't some debris or the filter itself that is interfering with the blower motor fan blades. Assuming those are not the cause, turn on the A/C with the filter removed and see if an air is blowing or if the motor appears to be spinning at all. If not, the motor fan blades could be getting bound for some other reason or the motor is dead.

I recently had to replace my blower motor due to the bearing going bad and making noise. When I installed the new aftermarket motor, I had it slightly tilted and it made a similar noise due to the blades hitting something. I then loosened the screws and retightened them when the fan was on and insured it was properly installed and no noise remained.

davidyal

Thank you Lexmus for the detailed reply. After a little testing, it appears that the blower is working, just the air is only blowing in the defrost mode direction. I'm suspecting it's the air mix servo now. Will start taking it apart to see if I can solve.

salimshah

Not the "mix" check the mode.

Mix controls temperature ( mixing cold vs heat) while the mode controls where the air comes out from.

You can move out of Auto and use the fan speed to check the blower speed, the mode to direct air to come from various ducts and you can always use the temp (auto/or_not) to control the mix servo.

Salim

davidyal

ok, this is going to be a late night.....

I got the mode servo out, and with the AC on and manually moving the cam arm (as if I were the servo). When it move it all the way up, I got flow at the feet, and all the way down it comes from the defrost. For the life of me, I can't find out how to get air coming out of the "in your face vents" next to the radio screen. What position should that be?

Since I heard a very loud noise originally, i'm wondering if the servo motor itself is burned out. I'm cleaning it now but not optimistic.

davidyal

Salim, you are so right, my typo. I' meant the MODE servo.