No heat or defrost in the car?

Tiny
BLADE751
  • MEMBER
  • 2001 TOYOTA AVALON
  • 0.5L
  • V6
  • 2WD
  • AUTOMATIC
  • 145,000 MILES
Hello, I have the car listed above XLS model with 170,000 miles. My problem is no heat no defrost. The A/C is working fine, both water hoses going into the heater core at the firewall wall is 130 degrees Fahrenheit so I know heat is there when I move the controls I can hear and feel the difference in air and hear the vents open and closing, I observed the Actuator Heater Blend Door Lever arm moving fully one way and then the other way when I depress heat and cold controls and still no heat. What should I look
for next?
Friday, November 10th, 2023 AT 2:04 PM

9 Replies

Tiny
JACOBANDNICKOLAS
  • MECHANIC
  • 108,230 POSTS
Hi,

I have a few questions. The vehicle can have automatic or manual climate control. Which do you have? Do you have dual climate control or single?

Have you tried removing the air mix actuator and moving the lever manually to see if heat is then felt?

Let me know. Interestingly, the hoses being the same temperature is questionable. One should be hotter than the other. I'm wondering if the heater core is plugged.

Let me know.

Joe
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Friday, November 10th, 2023 AT 8:44 PM
Tiny
BLADE751
  • MEMBER
  • 10 POSTS
Hello Joe, thanks for the response yes I have automatic climate control, yes I have dual climate control, no I haven't moved the air mix actuator by hand because there is an air duct that has a section that comes apart (in half) and I can see part off the flap
moving to horizontal and going back to vertical position every time the mix actuator motor and arm move when I press the temperature control button here is a pic of my control panel.
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Saturday, November 11th, 2023 AT 11:41 AM
Tiny
JACOBANDNICKOLAS
  • MECHANIC
  • 108,230 POSTS
Hi,

If you have a dual zone system, is it both sides that are affected? Also, I am assuming it is only temp that is affected and not the airflow direction, correct?

If you look below, it shows two actuators at different locations. This is why I need confirmation that neither side is working to produce heat and that neither the passenger's side nor the driver's side actuators are moving upon request.

Let me know.

Joe

See pic below.
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Saturday, November 11th, 2023 AT 9:01 PM
Tiny
BLADE751
  • MEMBER
  • 10 POSTS
Yes, a dual zone system, yes air flow direction is good, the only thing is affected is no heat on right or left side.
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Saturday, November 11th, 2023 AT 11:01 PM
Tiny
JACOBANDNICKOLAS
  • MECHANIC
  • 108,230 POSTS
Hi,

Unless both actuators failed at the same time, one side should be different than the other. I would recommend flushing the heater core to see if there is flow through it. The idea that the hoses are both 130F (at operating temp) leads me to think there isn't any circulation. The coolant, at operating temperature, should be approximately 200F. As a result, one hose should be closer to that temperature and the other slightly lower.

Let me know if that is something you are comfortable doing or if you have questions.

Take care,

Joe
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Saturday, November 11th, 2023 AT 11:22 PM
Tiny
BLADE751
  • MEMBER
  • 10 POSTS
Okay, sometime this week I will try that, I will let you know what happens.
Thanks Joe.
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Sunday, November 12th, 2023 AT 12:00 PM
Tiny
JACOBANDNICKOLAS
  • MECHANIC
  • 108,230 POSTS
Hi,

You are very welcome. If you have a chance, let me know how things turn out. I'm interested in knowing.

Take care,

Joe
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Sunday, November 12th, 2023 AT 7:24 PM
Tiny
BLADE751
  • MEMBER
  • 10 POSTS
Hello Joe, I finally got a chance to replace the thermostat and flush out the heater core and now I have my heater and defroster working, so a big (Thanks) to you for all your help. May God bless you and your family.
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Tuesday, November 21st, 2023 AT 2:29 PM
Tiny
JACOBANDNICKOLAS
  • MECHANIC
  • 108,230 POSTS
Hi,

That's great news and thank you for the update. I'm glad that took care of it for you.

Regardless, feel free to come back anytime in the future. You are always welcome here.

Take care, have a great Thanksgiving, and God bless you and your family as well. He watches out for all of us when we ask.

Joe
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Tuesday, November 21st, 2023 AT 8:52 PM

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