It could be the blower motor, control switch, relay (if your vehicle uses one), loose connection or bad fuse.
bad blower resistor
Most likely a failed blower resistor.
its the blower resistor.
Depends on what you mean by heater will not work. If the blower motor will not work, it can be a blown fuse, bad blower motor, bad blower motor switch, or a defective blower motor resistor pack. If you mean that the blower motor works but there is no heat, then it can be a clogged heater core, thermostat stuck open, or defective heater control valve.
check the fuse, the relay, the switch and the blower motor resister. If these all check out could be the blower motor its self is faulty
The heater blower switch and the electrical plug attached to it may be at fault. Remove the heater control unit from the dash and inspect the plastic electrical plug attached to the blower switch, you may see it has melted. The switch and plug is available from your local auto parts store.
blower motor resister is bad
There might be a bad fuse causing the heater to not work. Check the fuses if they are all ok you may have a bad blower motor. when you turn the heater on and no air is blowing then it is your blower motor.
the heater fan resister,it is or should be on inside or on outside heater box.
Bad resistor pack on blower motor? Bad switch?
You most likely will have a bad blower resister........
replace heater relay and or heater blower motor
probably the blower motor resistor
heater blower resistor has to be replaced. you have to remove glove boxthe resistor is to the right of the heater blower moter
If the heater does not work, check: -heater fuses and/or any heater relays -heater control head -heater blower motor resistor
Replace the resister, if that doesn't work replace the blower motor.
did your heater switch go out all of a sudden or did some work like high work and low not work? if some worked your blower resister is most likely bad under your glove box
You need to replace the blower motor resistor. I've been there done that.
check the fan switch.
fuse or relay most likely
Blower fan resistor under glove box...by passenger's feet...!
Buy a Toyota
Sounds like your dial/switch controal is shot or faulty. Try and replace that than see what happens. Just happened to me recently with the temp controal dial.
Replace blower motor resistor usually located in the duct work or out in engine compartment in ductwork by heater motor.
While there are a variety of reasons your Lexus ES350 heater is not working, the most common 3 are a broken heater blower motor, a problem with the thermostat, or a failed heater blower motor resistor.