How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site.
    Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask Chad Farhat Your Own Question
Chad Farhat
Chad Farhat, ASE Certified Technician A6 - Electrical / Electronic systems A7 Heating / Air conditioning systems
Category: Lexus
Satisfied Customers: 2535
Experience:  Owner at Carolina Auto Service & Sales , 20 years Experience in Foreign & Domestic Vehicles
45790705
Type Your Lexus Question Here...
Chad Farhat is online now
A new question is answered every 9 seconds

I have a 97 LS400 no air blows low .. I changed the

Customer Question

I have a 97 LS400 no air blows low .. I changed the resistor, Blower Motor and Climate Control unit.. Air and Heat works just can't change fan speed.. Please help
Submitted: 9 months ago.
Category: Lexus
Expert:  Chad Farhat replied 9 months ago.
Hi my name is ***** ***** I will be assisting you today
Expert:  Chad Farhat replied 9 months ago.
you replaced the blower & resistor and air blows low or it doesn't blow at all , do we have power to blower did you check with test light
If you changed these parts and runs low we need to check for a short .
Please let me knowChad ( aka-Customer
ASE Certified Tech
Customer: replied 9 months ago.
Verified blower motor works by removing it and reconnecting then powered on.. Left it out.. Changed Climate control same results.. Is there a Vacum line that can cause this?
Expert:  Chad Farhat replied 9 months ago.
Ok give a few minutes let me look up the circuit be right back with youi
Expert:  Chad Farhat replied 9 months ago.
You did change the resistor and still can't change the speed , was that blower motor resistor melted or burned when you changed it ?
Customer: replied 9 months ago.
No.. I've replaced it three times.. It worked once for about a couple of days back in March.. Trying to fix seriously now due to heat
Customer: replied 9 months ago.
Just got another relay switch.. Gonna try that
Expert:  Chad Farhat replied 9 months ago.
This one did it look burned , did you truly wiggling the wires at that connector while a/c switch is on and see if that makes it kick in in case connector is bad , I had a lot of case of bad connector then bad resistor or blower
Expert:  Chad Farhat replied 9 months ago.
Be back in few minutes
Customer: replied 9 months ago.
Nothing .. By the speed of the fan not changing I figured all I've changed .. It had to be CC.. Not! I can feel the AC.. It's cold but not blowing out
Expert:  Chad Farhat replied 9 months ago.

you have a broken blend door in the hvac assembly box , or when of the actuator that turns it , the gears are striped not all,owing the blend door to move to a full closed position and not allowing any hot air coming in, what you have now is cold air mixed with hot air , but your a/c is functioning, i m going to send you some diagrams to show what i m talking about , just give a little time to upload the diagrams and i will send them to you

Chad

Customer: replied 9 months ago.
Don't think so.. All Modes work.. Floor defrost and mix.. I can hear flap for outtee air or circular Air
Expert:  Chad Farhat replied 9 months ago.

something is not moving that door , the a/c is working, new blower & resistor , the cold air just can find its path to the inside cabin vents

if you have a capable scanner , you communicate with a/c module and run a actuator test on it

if not you will have to physically go in dash and inspect before you can determine what causing it , on this specific lexus , i have changed blower,resistor, climate control modules ,repaired a short and replaced broken doors in the hvac box.

chad ( aka _Customer

Customer: replied 9 months ago.
The gets into cabin.. Just at a very low speed...
Expert:  Chad Farhat replied 9 months ago.

do you hear the blower at least changing speed , i understand its low volume of air that is coming out is the problem, but does the blower changes speed when you change it with a/c control ?

Thanks

Customer: replied 9 months ago.
No
Expert:  Chad Farhat replied 9 months ago.

was that blower new or used?

Customer: replied 9 months ago.
Used
Expert:  Chad Farhat replied 9 months ago.

if you take out and power it up on the floor how fast does it go, it should be on full power with 12v on it .? does it , I want make sure we get this out of the way that blower is good

Customer: replied 9 months ago.
Blows high speed
Expert:  Chad Farhat replied 9 months ago.

but when u hooked to the car , does the speed of it is way lower comparing to be running outside by itself

Expert:  Chad Farhat replied 9 months ago.

was the climate control module used also , did u check the connector for burned spot melting , the one that gos in the back of it when you pulled it out , or all looked good?

+

Expert:  Chad Farhat replied 9 months ago.

1

Customer: replied 9 months ago.
All connections look good .. I'm going to connect fan outside of car on 12v
Expert:  Chad Farhat replied 9 months ago.

k let me know