No heat

[tsmart]

No heat. Car is not overheating. Hot water isnt making it to the heater. How involved to replace control door module?

[Guacamole]

Just to get to the heater core is a PITA. Are the blowers still working? Could be just a blockage in one of the pipes.

[ZUBAJA]

While I have removed engines out of 2 different Subarus, I really haven't messed with the inside part of the HVAC yet. There are several videos on Youtube that may help you though. Dennis

[tsmart]

Blower is working fine, only have 34000 on the car. (06 na) Radiator shows no rust, coolant tank full. AC works great.

[walfredo]

How are you so sure that "no hot water is making it to the heater"? (you can easily determine this by putting your hand on the coolant line running into and out of your fire wall and see if its hot). The more likely scenario is that, your temperature control isn't working, so its blowing cold.

First thing to check is to pull off your HVAC console (same process as removing the radio) and check to make sure the actuator on the back of your temp control is working. There is a cable that is connected to a wire hook that is pulled in and out by a plastic arm. That plastic arm can break (like it did for me). If it did break and there is still part of the arm left, you can drill a new hole in it (like I did) and put the wire hook into the new hole. If too much of the arm broke off, then youll need to replace the part.

If the actuator arm is working on the temp control, you then need to look at where the cable ties into your HVAC box (or check the cable itself), which is located under your glovebox. There is an actuator/flapper there which is controlled by the cable coming from your HVAC control. There is a clip that holds the plastic cable "sheathing" in place so the cable can move independtly of the sheathing. If that clip breaks or comes loose, the cable wont move the actuator/flapper. More info on this here (and many other places on different forums): https://www.subaruoutback.org/forums/11 ... e-fix.html

Lastly, if everything on the temp control side of things seems to be working, you are looking at the heater core or a blockage in coolant reaching your heater core, which seems to me as very unlikely. If your heater core is broken, this typically results in coolant leaking inside the cabin from behind your dash (along with a smell of coolant). Again, by touching the lines going into the firewall, you can diagnose if you in fact have hot coolant entering (and exiting) your heater core.

More than likely I am guessing its an actuator/cable/control arm issue as outlined above...

[tsmart]

I will check that out. I live in florida so havent used heat in a while BUT i replaced the radio over the summer..thanks..

[tsmart]

Both water lines are just a little warm, not hot at all. Before I remove anythin, another question...with ignition on, when i turn temp control to hot, shouldnt i be able to feel the cable move inside the sheath? Cause i feel nothing., no flex, no friction felt. Can i assume right there that cable isnt moving, and your diagnosis is probably right...makes sense so far...also if i take out glove compartment can i then physically move it? I can remove entire controller tomorrow..

[walfredo]

Yes there should be some resistance to your temp control knob. If it feels loose, its probably the plastic arm that is broken, exactly as mine did. Very easy to check. The clip for the cable sheath is also easy to find, its underneath your dash near the glove box. You should be able to trace the cable from the HVAC console to the clip and see if its still in place. For me, it was still in place, which lead me to check the plastic actuator arm behind the HVAC console. I think it would be unlikely that the entire cable would break inside the sheath so it must be the clip or the arm.

I do not think its necessary to remove the whole glove box (but I guess its not hard to do either way) as the clip should be visible by just looking underneath and identifying/tracing the cable.

[tsmart]

Welll, walfredo, you were entirely correct. The white linkage piece is broken off. But theres too little there to drill and reuse. How can i find the part number I need. Just describe it to the subie dealer? Thanks a bunch for your help!

[tsmart]

20181212_150604.jpg (2.72 MiB) Viewed 11158 times

[tsmart]

Flathead driver on broken controller

20181212_150720.jpg (2.43 MiB) Viewed 11158 times

Flathead driver on broken controller

20181212_150720.jpg (2.43 MiB) Viewed 11158 times

[tsmart]

Ok, that part from subaru is $137. It involves way more than the piece i need..Gotta fabricate something or just pay up...in pic, should i attempt a 1/16 hole on that stub? If so will i have full control of heat? I did not find the missing piece so dont know just how long control arm was. Can jb weld a hobby servo arm to stub?

[Guacamole]

Holy cow, would never have thought to check this.
If you don't feel like disassembling and fabbing, there's a few temp units on ebay for around $50.
Here's what it should look like though.

s-l1600.jpg (156.66 KiB) Viewed 11145 times

[tsmart]

Thats a much better pic, will check ebay and a local junkyard. I am in florida so not urgent, except wife would like me to put it back together. What would u call the whole thing, HVAC Controller?

[tsmart]

I am missing only the last quarter inch of that control arm.