1st gen: more climate control ??s

had the a/c checked & the climate control valve too... system is full charged, no leaks & so on. mechanic says the valve is working & that he thinks its a climate control problem.

he says this because even when the a/c is off.. i can be getting cool outside air & then suddenly i get HOT air.

same thing if i change the fan speed or move the position selector. cold to hot dial will make it hot & then maybe back to cool.

so could this be a control issue at the dash controls? or a damper control issue?

any of you experienced hands got input on this?

or does that expansion valve work on hot & cold sides?

this is not my area of expertise.

spill da tea! and Thanks!

sk

 

Sounds like the blend door actuator. Common issue with these trucks. Sometimes you can temporarily get them to behave again by changing from fully hot to fully cold several times. As far as I know the OEM part has been discontinued, but there are a few aftermarket options:

https://www.rockauto.com/en/moreinfo.php?pk=8757192&cc=1429084&pt=10721&jsn=851
https://www.rockauto.com/en/moreinfo.php?pk=12898897&cc=1429084&pt=10721&jsn=854

 

got em bookmarked & will try to check that thing out & see if its holding position or moving on its own.

thank you very much. gonna go look for a video of this to find location.

 

I have this same issue. With the AC off, it will go from blowing ambient air temp to hot air. Same with AC on, it will go from cold to hot and then if I'm lucky, after tapping it hard with my finger it would go back to cold air.

I used to be able to flick the knob with my finger and it would stop blowing hot air. Now that "trick" doesn't work anymore.

Not looking forward to another summer triple-digit summer temps with hot air coming out of my vents

 

glad to hear that im not the only person with this going on. now you have something to look for as well.

soon as mine comes bak will do the check on this & see if its that damper thing. if that seems to be holding steady? then maybe it is the control unit?

we had a beetle that had an issue like this & it was the damper door itself that was metal with a foam liner & the foam had dry rotted off of it.

 

If you have a friend with an 01/04 maybe swap the unit and see if the problem persists. I had something similar that I couldn’t pin point and the hvac control unit was cooked

 

ok spent this morning fiddling with this ....

that damper door positioning thing stayed everywhere i put it & never functioned wrong. now this was sitting still.

have no way of checking it while im moving. so no clue if this fixed itself or if its just hiding till its a blistering hot day.

 

update info:

driving around all day yesterday & every time it would switch to heat i did what another fella here said== tapped that control panel right under the a/c button & sure as shootin.... every time it instantly switched back to ice cold air.

if it was the damper door control down under the dash? tapping up there shouldnt have made a difference. right?

so im thinking it is that control panel or circuit board sending/losing signal to the damper control. gonna order a replacement for that thing & try that.

heres what i found: https://parts.lakelandtoyota.com/p/...el/3964066/5591035240.html?partner=googlebase

Part Number: 5591035240

does this look correct to you guys in the know?

 

guess we will find out cause i got a brand NIB unit on the way from Japan.

it was only $139 w/free shipping & once it shows up (couple of weeks) will put it in & eliminate this from the suspect list.

then if it does it again? will do that door control on the bottom.

 

Tadaaaa!

the unit showed up this morning & it was a quick simple job to take out the center dash plate & swap these out. fired her up & BINGO!!

so far, no combination of things that used to make it happen have had any effect! lets call this one : SOLVED!!

when you take this thing apart? it has a stud sticking in exactly where we all press on it at to get it to work. that stud goes all the way into the back of the rear section unit. which means=====

if it turns out that this doesnt fix it? it leaves that black plastic part on the back with the other circuit board in it as the culprit & it is also available from the same supplier in Japan.

either way this is fixable & there will be no sweating thru the summer in Taco.

PS: did this while working on another thing in my other thread. (power steering leak)

 

update===== 5/26/23

still working perfectly in all conditions!!

it could go to crap at anytime..... but so can anything. will post back in this thread if it takes a dump.