Temperature control clicks

[eanema]

Hi Guys,
I've got a 1998 SR5 with manual temperature control.
I've been doing some homework on this site and read a few threads about people with stuck blend doors (the white linkage on the passenger side below the glove box) others with stuck coolant mixer valves (not sure what its called - the one under the hood on the top of the firewall)

Anyway, as with the OP in this thread:
http://www.toyota-4runner.org/3rd-gen-t4rs/22490-heater-control-question.html
it was a cool day and my wife wanted some heat in the vehicle (I more than likely had all 5 windows down haha) and it started to click in her hands, just as it has for so many others. Seems to be the plastic teeth of the actuator mechanism inside the dash skipping across the gear its meshed with.

Anyways, in an attempt to troubleshoot the problem I open up the dash and pulled the climate control console out (still connected to the cables though) and attempted to figure out which cable was attached to the temp control dial. I found that there were two cables the moved with the dial, one that goes to the blender door below the glove box and another cable that went to mixer valve under the hood.

The mixer valve was a little stiff, but nothing crazy - I took the lever off and lubricated the mechanism and the thing is smooth as butter now. But the dial still clicked when I turned it. I also took the cable off the blender door and actuated it by hand. There was so little resistance there that it couldn't possibly be an issue.

So then as a test I removed the cable from the mixer valve and from the blender door and then tried to actuate the dial - still clicking. This tells me that its a problem either with too much resistance in the cables, or a problem within the plastic cable-pull housing in the dash.

Does anyone have any experience with this? I'd like to remove the climate control console and open it up and have a look inside but I can't figure out how to remove the cables... anyone know what this is worth to replace? Or part numbers etc? any advise on this would be great...

Thanks All

 

[eanema]

bump bump, its getting cold up here at night...

 

[JRZEE2000TR4LTD]

bump bump, its getting cold up here at night...

So, you removed the ends that go to the blend door and the heater control valve? When you turn the dial, do the cables move in and out?

 

[eanema]

With both cable ends removed from the blend door and the heater control valve, when I turn the control knob the cables do move in and out. I can't extend it much past 1/3 of the way out though because it starts to click

 

[JRZEE2000TR4LTD]

With both cable ends removed from the blend door and the heater control valve, when I turn the control knob the cables do move in and out. I can't extend it much past 1/3 of the way out though because it starts to click

Where is the clicking coming from? Can you remove both ends and pull each cable in and out manually?

 

[eanema]

The clicking seems to be coming from behind the dial. It sounds like there is a plastic gear that is skipping across another plastic gear it meshes with.

I tried to take it out a while ago, but it was not obvious how the cables were connected to the dash unit. I had it completely out except that the cables were still attached. I was in a bit of a rush before when I dove into this before, so I may have missed something, but if you can tell me how these cables attach to the dash controls I would appreciate it.

I'd like to take the thing out of the dash and put it on my healing bench, rip it apart and see if something has broken inside. Maybe I can glue it back?

 

[JRZEE2000TR4LTD]

The clicking seems to be coming from behind the dial. It sounds like there is a plastic gear that is skipping across another plastic gear it meshes with.

I tried to take it out a while ago, but it was not obvious how the cables were connected to the dash unit. I had it completely out except that the cables were still attached. I was in a bit of a rush before when I dove into this before, so I may have missed something, but if you can tell me how these cables attach to the dash controls I would appreciate it.

I'd like to take the thing out of the dash and put it on my healing bench, rip it apart and see if something has broken inside. Maybe I can glue it back?

Does this look familiar on the back of your control? Sounds like the clicking is coming from the control head. I have a 99 Limited so my head unit is different. I know ebay has a crap ton of those units for cheap with the cables included. If it's clicking it's probably stripped or broken somehow and there will be no fixing it.

 

[eanema]

Nope, that doesn't look too familiar to me... I think your right about having to replace it though. It does sound like there is broken plastic. I'll have to have another look at it and see if I can get the cables removed.

Thanks for the info

Sent from my Pixel 2 using Tapatalk

 

[eanema]

So I know this is a little late, but I wanted to give an update. Last September I did rip it all apart and fix it up. I took a bunch of pictures as well that will probably be of interest to anyone who is also having this problem.

It's not difficult to remove the temperature control box from your dash, just remove the front bezel, then a few obvious screws. The hard part for me was figuring out the correct way to remove the cables from the control box. I ended up breaking a few important plastic tabs that hold the cables down. When I put it all back together I used stainless steel lock wire and epoxy to hold it in place. The correct way to remove the cables from plastic housing is to press the inner tabs outward while pulling up on the cable - not too hard though don't want to break them off. If I remember correctly now, I believe I broke off some of these tabs once I had figured out how to remove the cables. The plastic was just old and tired...

Once I got the box out, and on my desk I opened it up. It was clear why it was clicking. The plastic bushing that holds the dial gear engaged with the actuator gear inside the control box was broken and not retaining anything. Take a look at the images attached. My solution to this was to use stainless steel lock wire to wire the bushing tight. This actually worked well, and would have been a simple/easy fix if I hadn't broken a bunch of the plastic clips holding the cables to the control box. Now, 6 months later and some of the coldest weather I've seen in a long time - it dropped down to -40c for a few days a little while ago (that's also -40F) and it didn't break. I'd say its good enough for another 20 years of service, right?

 

[alumarine]

Good write up, thanks!