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 sprinkles08 Your Own Question
sprinkles08, ASE Certified Technician
Category: Lexus
Satisfied Customers: 21410
Experience:  ASE Master and Advanced level certified. Factory trained with 15 years dealership experience
Type Your Lexus Question Here...
sprinkles08 is online now
A new question is answered every 9 seconds

Lexus RX 350: AC Blower motor does not work. Checked the wire

Customer Question

AC Blower motor does not work. Checked the wire harness connecting to the blower motor and did not find 12 V voltage. fuse is fine. wire harness does not seem broken
What is wrong ? What do I need to replace
Submitted: 6 months ago.
Category: Lexus
Expert:  Vladgmru replied 6 months ago.
Hello and welcome to JustAnswer.My name is ***** ***** your description, it sounds that you have a problem with the Blower Motor Controller( it is also called Blower Motor Resistor).That part usually controls ground path to the blower motor so if you checked for 12v between two terminals at the blower motor connector, then try to check each terminal separately but use any bare metal part of the car as ground and see if you have 12V ( car should be running and heater should be ON as +12V usually supplied by heater relay).If you have +12V on one of the terminals at the blower motor connector, then it is very likely you need a new Blower Motor Controller/resistor
Customer: replied 6 months ago.
I am sure I have good ground because the grounded pin is grounded. I verified this by checking the it against the bare metal of the car. So I'm not sure it is not the ground. I am missing the +12V.
What is the part number for the heater relay? How do I replace it?
Expert:  Vladgmru replied 6 months ago.
Unfortunately I can't access to exact wiring diagrams for 2011 model year, so by checking 2008 model year ( I really hope they have not changed much) +12V to the blower motor and blower motor controller is coming from 50A heater fuse and then via the heater relay when the relay contacts are closed= relay energized.The relay appears to be a standard relay located in the engine compartment Right relay box , jusst next to the horn relay.
Customer: replied 6 months ago.
Is the relay located in the same area as the fuse box? I would appreciate it if you could give me 2011 information.
Can you give me the part number for a standard relay?
Are they easy to replace?
Customer: replied 6 months ago.
Also, is the heater relay only supplying the blower motor and nothing else? If not, how come I dont see other things failing because of the missing +12V. Only the blower motor failed.
Expert:  Vladgmru replied 6 months ago.
Looks like I can't get 2011 information.I am trying to help you basing on 2008 and I am honest with you. I hope it has not changed and at least it is worth to try.No need to replace anything at this stage. Use a test light, connect the alligator clip to a known good ground and probe each terminal at the blower motor connector ( red and yellow wires) with the engine running and heater ON and blower on as well. see if you have +12V.If you get +12V to the motor, then it is likely you have a problem with blower speed controller.If you do not have +12V to the motor , then need to check 50A fuse and relay.The relay appears to be in separate relay box ( not with fuse) and that box should be on the RH side in the engine compartment.According to the 2008 diagram, the relay feeds the motor and motor speed controller ( red wire).
Customer: replied 6 months ago.
2008 (2nd gen) is an older generation car than 2011 (3rd gen). My wires are white/black (ground), blue(blower motor speed controller), and white(+12V). This leads me to suspect things are different for 2011 than 2008.If you dont have the 2011 information could I get another expert please?
I need the part number and location for the heater relay in 2011. Thank you
Expert:  Vladgmru replied 6 months ago.
Ok, that makes sense. I am going to opt out and open your question to other experts.Sorry I could not help you.
Expert:  sprinkles08 replied 6 months ago.
Hello and welcome to JustAnswer!The blower motor is powered by the 50 amp fuse labeled HEATER. Has this fuse been checked?
Customer: replied 6 months ago.
Hi, This fuse has been check and it is fine.
Whats the next possible cause?
Expert:  sprinkles08 replied 6 months ago.
Is there power at the fuse?
Customer: replied 6 months ago.
Yes There is power. Does that mean its the relay?
Expert:  sprinkles08 replied 6 months ago.
If there is power at the fuse and the fuse is good then that does indicate an open circuit in between. The wire is blue as it leaves the fuse box and changes to white at a connector in between, and is white at the motor. In the left kick panel there is a row of connectors. The third from the bottom should be a three way connector where you'll find this circuit. You can see if you have power to that point to determine whether the break is between the connector and fuse box, or the connector and blower motor.
Customer: replied 6 months ago.
Thanks. Can you share the wiring diagram? also. where is the left kick panel exactly if I'm sitting in the driver seat?
Do I have to remove any trim ? Thanks.
Expert:  sprinkles08 replied 6 months ago.
I'm unable to post material directly from the service information due to copyright.The kick panel is the trim panel to the left of the floorboard.
Customer: replied 6 months ago.
OK. I just want to understand if there is a heater relay. But it sounds like there isn't one. Can you confirm?
Also, what's the best way to remove the kick panel trim
Expert:  sprinkles08 replied 6 months ago.
There is not a relay in question. If there is power at the fuse but not at the blower motor then you have an open circuit in the wire.The sill plate needs to be removed first by pulling is straight up to disengage the clips. There will be one screw on the kick panel behind a small cover that pops off, and then the panel's clips can be popped loose and the panel removed.

Related Lexus Questions