DIY: Heater core replacement in BD/BG/BK

[Dead91silvia]

Yes, I was dumb enough to actually do this on my own car...

Difficulty level 1-5

5 for pain in the ass!

I decided that after year of the slight smell of coolant and the windows starting to fog, it was time to change the heater core out. I have had a new one sitting in a box for the last few years...

If you are a beginner, DO NOT try this! If I wasnt short of work and had the money to take it to the dealer, I would have in a heart beat!

REMOVE BATTERY TERMINALS and cut all power to car!!!!I dont want to hear that an airbag blew in your face....
https://sl-i.net/FORUM/images/imported/2012/02/IMG_8649-1.jpg

Started at 10AM... 10:00 hours to you military guys... Let it begin!
https://sl-i.net/FORUM/images/imported/2012/02/IMG_8621-1.jpg

Removed front seats... Move room to work.. If you dont already know how to take out the seats, put the tools down and stop right now!
https://sl-i.net/FORUM/images/imported/2012/02/IMG_8622-1.jpg

Pull the center console... 9 screws...
https://sl-i.net/FORUM/images/imported/2012/02/IMG_8624-1.jpg

If you dont know how, this is the shifter release...
https://sl-i.net/FORUM/images/imported/2012/02/IMG_8625-1.jpg

https://sl-i.net/FORUM/images/imported/2012/02/IMG_8626-1.jpg

Pull stereo bezel... 2 ash tray screws and cup holder screws... unplug cig lighter...
https://sl-i.net/FORUM/images/imported/2012/02/IMG_8627-1.jpg

https://sl-i.net/FORUM/images/imported/2012/02/IMG_8628-1.jpg

https://sl-i.net/FORUM/images/imported/2012/02/IMG_8629-1.jpg

Remove stereo... Dont forget about the screws way in the back....
https://sl-i.net/FORUM/images/imported/2012/02/IMG_8630-1.jpg

Vent trim... Pull out easy... unplug 4 ways switch...
https://sl-i.net/FORUM/images/imported/2012/02/IMG_8631-1.jpg

Glove box... 2 screws at bottom, then remove inner backing plate...
https://sl-i.net/FORUM/images/imported/2012/02/IMG_8633-1.jpg

https://sl-i.net/FORUM/images/imported/2012/02/IMG_8635-1.jpg

There is a few 10mm bolts in there...
https://sl-i.net/FORUM/images/imported/2012/02/IMG_8654-1.jpg

Remove cluster bezel... 4 screws... remove switches... I had to cut the wires for my alarm light, thank you so much Subaru America for HARD wiring my damn light! :smt013
https://sl-i.net/FORUM/images/imported/2012/02/IMG_8636-1.jpg

Remove Cluster... Unplug everything, there are 4 plugs if I remember right...
https://sl-i.net/FORUM/images/imported/2012/02/IMG_8639-1.jpg

Remove 4 screws for HVAC
https://sl-i.net/FORUM/images/imported/2012/02/IMG_8641-1.jpg

https://sl-i.net/FORUM/images/imported/2012/02/IMG_8641-1.jpg

Pull the lower dash cover... 2 screws...
https://sl-i.net/FORUM/images/imported/2012/02/IMG_8637-1.jpg

[Dead91silvia]

Time for the dash... :smt009 I'm sure I missed a few here, but you will get the point...

Top cover is tricky... It's better to damage the little cover then the dash. Use something flat to pull up, do not pry up as it will damage the dash pad...
https://sl-i.net/FORUM/images/imported/2012/02/IMG_8643-1.jpg

https://sl-i.net/FORUM/images/imported/2012/02/IMG_8644-1.jpg

Cover removed... 2 10mm bolts...
https://sl-i.net/FORUM/images/imported/2012/02/IMG_8645-1.jpg

https://sl-i.net/FORUM/images/imported/2012/02/IMG_8646-1.jpg

There is one of these on each side of the dash... 10mm bolts...
https://sl-i.net/FORUM/images/imported/2012/02/IMG_8648-1.jpg

Remover steering column bolts... 2 12mm... (Also no pic, remove column shaft bolt on rack)
https://sl-i.net/FORUM/images/imported/2012/02/IMG_8655-1.jpg

The dash should now be free.... Time to unplug a butt load of stuff!
Passenger Airbag needs to be unplugged... MAKE SURE THE BATTERY IS DISCONNECTED!!!!
https://sl-i.net/FORUM/images/imported/2012/02/IMG_8657-1.jpg

A pile of plugs on driver side... Also the HVAC, Stereo, and other random things...
https://sl-i.net/FORUM/images/imported/2012/02/IMG_8660-1.jpg

This is what you should have out....
https://sl-i.net/FORUM/images/imported/2012/02/IMG_8663-1.jpg

I opted to have the HVAC unit still hooked to the car, or heater box...
https://sl-i.net/FORUM/images/imported/2012/02/IMG_8665-1.jpg

Dash should be ready to be pulled... now time to remover the cross bar... 4 12mm nuts and bolts of driver side, 2 12mm nuts on passenger side. 2 10 mm nuts behind Airbag Control unit, 4 security bolts for ABCU...
https://sl-i.net/FORUM/images/imported/2012/02/IMG_8661-1.jpg

https://sl-i.net/FORUM/images/imported/2012/02/IMG_8666-1.jpg

https://sl-i.net/FORUM/images/imported/2012/02/IMG_8676-1.jpg

https://sl-i.net/FORUM/images/imported/2012/02/IMG_8667-1.jpg

https://sl-i.net/FORUM/images/imported/2012/02/IMG_8674-1.jpg

https://sl-i.net/FORUM/images/imported/2012/02/IMG_8675-1.jpg

Now for the hardest part! You think I'm joking huh.... Yeah, no joke getting the box off the fire wall is crazy hard! There are a few 10mm nuts and bolts that hold all the boxes to the fire wall. This is where I kinda gave up on pics and procedure. It is ether glued to the fire wall, of the fire wall insulation melts and holds the heater box to the wall. This makes it really hard. I left the AC box alone since I have no need to service it at this time and thats more money.
https://sl-i.net/FORUM/images/imported/2012/02/IMG_8669-1.jpg

The glued stuff....
https://sl-i.net/FORUM/images/imported/2012/02/IMG_8670-1.jpg

One split heater box...
https://sl-i.net/FORUM/images/imported/2012/02/IMG_8671-1.jpg

And the new core... You remove the pipes from the core and reinstall...
https://sl-i.net/FORUM/images/imported/2012/02/IMG_8673-1.jpg

Ok... So if you have really got this far, you can figure out how to put it back together. In truth, it goes back together much easier then it comes apart. If you have a Dealer installed alarm, know that you will be cutting a few hard wired wires. This is a big job and I worked on it for about 9 hours with only a short 30min brake.

This is a job that you can do, but at your own risk! Hope this helps someone... :smt023

[krot84]

Thanks and good luck man!! That's exactly what i was waiting for.
And you're not dumb you're just an enthusiast like all of us :)
Hopefully your DIY will give me the courage to do it myself.

[Dead91silvia]

Thanks... Like I said, if I had the money to take it to the dealer, I would. This is a big job. As of now, everything is working like it should and completely finished.

If you do decide to do this, make sure you do this in one day, if you dont, you will forget a lot of things. I started to forget by the time I was starting to re-install everything.

[krot84]

At least i don't have to worry about an air bag exploding in my face 'cause i don't have any. LOL

[Dead91silvia]

Huh?! Do they not have then over there?

[krot84]

I think they were just playing cheap when the car was imported, the same with the awd, my car is fwd. go figure...
Another thing, why did you remove the center console and the sits ?

[Dead91silvia]

Taking out the seats and console gave a LOT more working space that you will need. Also the dash needs lots of space to come out. It's only a little more work to make your life that much easier!

[eekay]

Awesome! Great DIY, Dead91! I'm glad you decided to do it. :)

[nikolaus.conrad]

I needed to do this for my first Subaru, I tore apart a car at my junkyard to get the core, such a pain in the ass. Then a few days later someone hit me and totaled it :smt021

[Wiscon_Mark]

Great DIY!!

I'll add this to the threads of note.

One little warning for everyone: Do not disconnect the sleeved cable that is used to control the heat/cool air at the HVAC controls side - it's impossible to get back on without breaking things. The OP didn't disconnect anything here, but if you want the HVAC controls out of the way, disconnect the cable at the heater manifold style (under the dash). It's much easier to reconnect.

I made the above mistake when I took apart my HVAC controls to do lights.

[eekay]

Are you talking about the E/C clips that connect the temperature selection slider on the HVAC? I've disconnected this before, but never under the dash. I'm going to have to pull all this stuff apart soon though. So, I suppose I'll find out! ;) Thanks for the heads up.

[Dead91silvia]

Yeah, if you do pull the HVAC unit, take it off the box if you need to. So much easier, but only if you have to. I left it as it was less work and less parts to miss place! hahaha...

And thanks guys... I'll work on a few more if I have the time. Next big on is the headliner in my BH and also in my BD... sigh....

[grayguy]

where do you buy that stupid ABS module socket? I've always just taken them out with vise grips.

[Dead91silvia]

haha! Harbor Fright has a cheap ass set I got for like 6 bucks (looked at 5 sets before finding a complete set that was drilled straight). All they are is security torques. I'll get a nice set someday, but they come in handy.

[eekay]

ABS module socket?! Pics?

[grayguy]

I am fianlly gonna do this to my car this weekend. Super not looking forward to it. But alas, so much cheaper than paying for it

[Odycee]

Would you go over details how to disconnect that AIRBAG yellow/green connector? I always fought with it and never could get it out. Push the yellow connector down, slide it to the left?

[Dead91silvia]

If I get some time and also get well from being sick, I'll see if I can take some pics or take a vid.

I completely forgot I even did this DIY... haha

[Odycee]

Get well and thanks the DIY video coming later.

[grayguy]

Well, today was the terrible day. I have just over 3.5 hours into pulling the dash/blower box/heater box, replacing the core and blower motor, swapping the dash harness onto a new dash, and reinstalling it all. I think I'll have about another hour into it when I got back tonight to hook the harness all up and put it back together.

Sent from my SAMSUNG-SGH-I537 using Tapatalk

[Patrick Olsen]

Excellent write-up. I just pulled mine out, and figured I would add a couple pics to fill in where you gave up on pics. :p


Now for the hardest part! You think I'm joking huh.... Yeah, no joke getting the box off the fire wall is crazy hard! There are a few 10mm nuts and bolts that hold all the boxes to the fire wall. This is where I kinda gave up on pics and procedure. It is ether glued to the fire wall, of the fire wall insulation melts and holds the heater box to the wall. This makes it really hard. I left the AC box alone since I have no need to service it at this time and thats more money.


After I drained the cooling system, I pulled the heater hoses off the hard lines at the firewall, and then I stuck a couple of vacuum caps backwards into the hard lines to seal them and keep any residual coolant from leaking out inside the car:
https://sl-i.net/FORUM/images/imported/2015/05/heater20core42020engine20bay-1.jpg

As you said, only 3 bolts/nuts hold the heater box in place, and there's a harness to unplug on the driver side:
https://sl-i.net/FORUM/images/imported/2015/05/heater20core2-1.jpg

https://sl-i.net/FORUM/images/imported/2015/05/heater20core3-1.jpg

https://sl-i.net/FORUM/images/imported/2015/05/heater20core52020harness-1.jpg

Like you, I found the heater box did NOT want to pull away from the firewall. I was pulling and prying, but something seemed stuck. Kind of on a whim, I took a can of spray silicone lubricant (which is great for breaking loose things like old rubber exhaust hangers) and sprayed that on the hard lines and the firewall seals in the engine bay. Went back in the car, pulled on the heater box while rocking it back and forth a bit, and it came right out. So I think in my case what was holding the thing in place was the rubber firewall seals being stuck to the hard lines.

https://sl-i.net/FORUM/images/imported/2015/05/heater20core62020removed-1.jpg

Edit: When I went to actually pull the heater box out of the way completely, I found that there is an additional harness to worry about, located lower on the heater box than the harness I showed before. In this case, the harness is mounted to the box, so you remove it by removing the phillips head screw in the 2nd picture:

https://sl-i.net/FORUM/images/imported/2015/05/heater20core8-1.jpg

https://sl-i.net/FORUM/images/imported/2015/05/heater20core7-1.jpg

[Patrick Olsen]

I pulled the heater core just to get access to the wiring, but now that I have it out, I'm wondering if I should go ahead and replace it. Part of me thinks, "If it ain't broke, don't fix it," but part of me thinks the car's got 240k miles or so on it and I might as well swap the thing out while I'm here.

For those that have done this, what replacement heater core did you use? I see the OEM one (72130FA002) lists for $317 (:smt119), while aftermarket ones are available on Rock Auto for under $50. I'm all for using OEM parts, but that price difference is pretty ridiculous.

[Dead91silvia]

Nice! I just got fed up with taking pic and I wanted to get it done when I stopped snapping pics... haha... The core I installed was about $79, but I also got it back in like 2008 and it sat in a box for years.

[Michelle]

https://sl-i.net/FORUM/images/imported/2012/02/IMG_8639-1.jpg

Disconnect battery, he says. Hmm...

Kidding. This is a great thread. I may need to reference this later if I do a harness merge. And thanks, Patrick, for the tip about the silicone! I've been following your thread on corner-carvers!

[Dead91silvia]

LOL... Do as I say, not as I do. ;)

[meepers]

Disconnect battery, he says. Hmm...

That right there is GOLD!