Heater not blowing hot air

[pecos]

New to me 01 4runner sr5. Heat has never worked for me.

Set dial to hot and turn up fan...blows cool air. Nothing warm at idle. Nothing warm while driving. No noises or leaks.

I just fixed this a similar issue in a nissan armada 1 week ago. Fix for it was replacing the heater control valve.

The toyota heater control valve is different in that its manual vs having any electronics. Am I right by saying that? Should I be able to manually move it with my hand? There is a cable on it, what actually moves the cable? A solenoid?

After reading other forums and threads I was also thinking about the heater core. Not sure why I was thinking as this is the issue but its basically the worse part to replace. How do you know if your heater cores is bad? If rust is in there when you flush or clogged.

Thank you in advance.

 

[spartacus]

New to me 01 4runner sr5. Heat has never worked for me.

Set dial to hot and turn up fan...blows cool air. Nothing warm at idle. Nothing warm while driving. No noises or leaks.

I just fixed this a similar issue in a nissan armada 1 week ago. Fix for it was replacing the heater control valve.

The toyota heater control valve is different in that its manual vs having any electronics. Am I right by saying that? Should I be able to manually move it with my hand? There is a cable on it, what actually moves the cable? A solenoid?

After reading other forums and threads I was also thinking about the heater core. Not sure why I was thinking as this is the issue but its basically the worse part to replace. How do you know if your heater cores is bad? If rust is in there when you flush or clogged.

Thank you in advance.

If the coolant level is good. Then the servo motor might have gone bad and not pushing the arm over to let in the heat. Bad servo motors make a clicking noise in some intances. The valve let's coolant flow to the heater core you can open it manually. There is actuator under the glove box that controls it.

 

[pecos]

Bare with me...How/where do I check the coolant level?

Ok, so a servo motor is what moves the heat valve arm.

I am not hearing any noises.

When you say actuator is that the servo motor or are those two different items?

 

[spartacus]

Bare with me...How/where do I check the coolant level?

Ok, so a servo motor is what moves the heat valve arm.

I am not hearing any noises.

When you say actuator is that the servo motor or are those two different items?

The actuator arm that controls the cable on the heater water control has a motor on it under the glove box. Check the coolant level in the over flow reservoir it has markings.

 

[19963.4lsr5]

The actuator arm that controls the cable on the heater water control has a motor on it under the glove box. Check the coolant level in the over flow reservoir it has markings.

Or pull the Rad cap with a cold engine and make sure coolant is touching the underside of the Rad cap.

Even if your tank is up to the cold mark it’s worth pulling the cap.

If your tank is full and you have an air pocket under the cap you have an antifreeze leak or a bad Rad cap or something is wrong with the hose between the fill neck and the tank.


Sent from my iPhone using Tapatalk

 

[alumarine]

The heater control valve is in the engine bay on the top middle of the firewall.

You can remove the cable that goes to it and move the valve one way or the other to see if that allows the heat to work.

 

[pecos]

Yes, I know where the heater valve is. I will remove the link and move it and then test. UPDATE: One of the ends of the heater value is disintegrating. I tried to take the hose off and inspect closer. That component needs to be replaced. Will get a new one. It the arm does swing freely meaning its operational.

I did notice trying to move the cable...I could not move it. Almost seemed seized or binding.

See attached picture of over tank. Has about 2 inches of fluid in it. Is that correct?

I removed cap to radiator....its full to the top. No milkshake.

 

[3bears]

without going out to my rig. something looks different about that overflow tank. aftermarket ? There should be marks on it for cold and hot. If not , my tank when hot is a bit more than half way full.

there is another thread running on heater control valves. some out there are junk.

with the cable disconnected you should be able to turn your heat control on and see if cable moves....if it does than you have/had a bad valve that is jammed up.

 

[pecos]

My overflow does have a F for full and L for Low marking on it. Picture is not great.

And if I turn on my heat control and the cable does not move? The servo motor could be bad? I think the heater control valve is fine besides the end breaking off. Arm moves easily. New one will be here in two days.

What is the actual servo motor name called?

 

[pecos]

Turn on heat control…. Cable does not move. No sounds coming from servo motor. See pics below.

Having trouble loading pics from phone. Part is located front passenger footwell… left side

 

[pecos]

I removed the servo motor under the glovebox. Strangely I unscrewed 2 screws and it came out. I did not have to unplug it. Appears it was not plugged in. I mean clipped in! Why? Not sure.

Before plugging it back in, I tested movement of cable to make sure it was not seized, etc. It moves fine.

I decided to open up the servo motor to investigate. All looks good. Gears are fine. You will notice in the picture below that a screw on the outside was not screwed in all the way. Why? Not sure. Also, only 1 screw existed holding it together. I would think there should be 4.

Notice in the first pic the white arm...has a metal nipple on the end...there is a little plastic part on it that is worn..cracked.

I plugged it back in to test the heater control and cable movement. Moving from cold to hot and back moves the cable.

Waiting on the new heater control valve which should be here tomorrow and will reassemble everything.

 

[3bears]

good luck. thats a positive good luck. keep us posted

 

[pecos]

I installed the new heater control valve. I did not connect the cable. I kept the valve in the open state. Open means hot water is flowing right? Both sides of the valve hoses are hot.

I have the server motor disconnected to eliminate it pulling the cable.

Drove the car with heat knob turned to on.......still no heat.

Am I testing this correctly? I am not sure I am.

Is there a blower motor for the heater and for the ac? or is it just one that blows for both systems?

 

[pecos]

Decided to put everything together for a true test....

I have hot hot air now!

HOWEVER, I turned on the AC.....I still have hot hot air....and a loud buzz noise coming from the passenger footwell...its the servo motor....makes sense now why it was disconnected.

It does move as I stated in another post...but connected up it makes a noise...so I assume that part is bad? Unless something else is jamming before it. What do you think, buy the part?

I did call autozone and o'riely's yesterday about this part and its on back order everywhere. I can get it new on ebay.

Before I buy the servo motor is there anything else that could be jamming it or causing that noise? When i connected the servo motor via the electric plug it moved fine, no noise. Not sure what the noise means...is it jamming or is pulling the cable too much of a load?

I thought the plastic gears look fine when I looked at it before...I will look again.

Found this....
Strange buzzing sound from cabin

 

[pecos]

Update:

So I was able to get a new servo motor from autozone. I was able to find an alternate part from another thread.

2013-2014 CADILLAC ATS RH RIGHT TEMP VALVE ACTUATOR 22799393 -> $28.92
Denso Part N0: AW063700-8590

Today's cost was around $40. It was not a complete plug n plug part. On the new unit, I ended up replacing the new longer white arm with the original shorty white arm from the old unit. I am not sure I have the placement of the arm correct. So am I opening and closing 100%? Not sure. Maybe 90-95%? Not sure.

Appears to work. I have hot and cold air. If it stops working I will get the correct part next time. I will test more this week.

I was wondering what I should call my 4runner. I think Caddy will work.