Faulty blend mode for the HVAC.

[Scubamares]

Hi. I have a land cruiser j120 2007 with dual zone temerature control.
The problem is that i have warm air coming out of the vents on driver side, but on the passenger side it only blows cold air, or outside temp. In all modes.
When i use the front window mode, warm air is coming up on the left side, but cold air on the right side.
I googled it and found out there must be an error with the blend door actuator.
But that doesnt seem to be the case. Please take a look at the videos.
I hope someone can explain to me whats going on and how to fix it.

The blend actuator works just fine, doesnt it?:

The blend door is ok, it shuts when i pull it up.

The other door is not loose.

There is nothing blocking the heater radiator.

The driver side gets warm as it should.
The pipes to the warmer radiator is hot on the driver side.

I got into the system check mode, but didnt find anything interesting there. Is there anywhere i should look?

I also have the obd2 reader, but doesnt know what to look for.

 

[Scubamares]

Ok.

No help from this forum, but i fugured out the fault myself, and will post it here so anyone else that have the same problem as me can figure out the issue. Its easy and cheap. I spent 20 bucks. The workshop Said that it would cost 5.000 bucks, they wanted to change the heat core.

I Just had to flush the heat core.
Take off the pipes that goes into to heat core from the front, the one that goes into the torpedowall.
Put two hoses on, and blow in the BOTTOM pipe. This is the pipe where the water usually comes out from the heat core, you want to flush it backwards.
When you get nothing but air out, fill it with radiator flush / cleaner. Let it sit there for a while.
Blow out all the mixture and rinse it good.
Fill it with new antifreeze.
Remount, and you are warm on your next drive.

I mounted a sirculation pump and a heater, to flush it the best way.
I used a filter to take out all the dirt. I let it go for 3 hours, with the temperature og 85 deg c.

After i remounted it, i had more heat that ever before.

Never mind the Heineken, that was for me, not the car.

 

[kerlo]

Mate, this is absolutely incredible!

I have the same problem with my 2005 Prado 120 and over the time I have visited several mechanics, all giving up in the end. Not having any suitable space only steps I could have done myself was to check movement of the actuators and then I removed, checked, disassembled and re-greased them, but to no avail.
I started suspecting the heater core of course (and tubes, etc) now. Interestingly, I suffered this issue one winter, next winter it was much better and this year it is very bad again, hence I started to look for a solution. And now I have found this gem!

One thing I've noticed recently is that if I poured in a little more of coolant passenger air temperature changed somehow. I reckon it could be that resulting pressure somehow pushed more coolant through?
Since I have no space to perform this task I will have to find someone to do it for me. Is there anything else that comes to your mind that can be added or clarified to help the process?

You also mentioned the circulation pump with some heater attached to it. Could you please elaborate a bit on this set up, where did you get it from, etc?

And one last thing, what kind of coolant do you use?
As far as I know Prado 120 should take Toyota super long life coolant (mine is pink), but this original Toyota one is not always so easy to find. Most people in Europe use just normal G12, G12+ but it is actually not fully up to specs as it it lacks phosphates. I also suspect that these issues might be somehow connected with usage of this not fully up to specs one over the time.

Thanks again!
Pete