2013 hvac fried (now with images)

[pikker]

I posted an issue over in the newb section, and now I've finally found the issue and it's a big one. This is a 2013 Impreza, out of warranty.

Lost my high fan setting a while ago. Then all speeds died a few days ago.

1. Checked all fuses (fine)
2. Replaced the resistor (original was corroded) figured that was it. Nope.
3. Called my dealer, told me swap the relay. Still didn't work.
4. Put in a new blower motor. (Still nothing)
5. Pulled out the controls from the console...holy crap!

The molex on the loom side was melted and fused to the controls! Finally pried them apart everything is toast. Even the wiring directly behind the molex melted! All this with out blowing a fuse??

So the controls are 300+ from Subaru. I can get a scrap set for under 100 but I'm not sure I should after seeing this. No idea what wiring and a plug will be.

I'm long out of warranty but I wonder if I should still contact them the damage is incredible.

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[pikker]

Dealer just quoted me 12 hours of labor and a new main harness for 2 grand!

Wondering if corporate could work out something? No tech at the dealer ever saw the wiring fried like this.

[Cougar4]

It would be good to know what caused the trouble and fix it so it doesn't happen again. As far as I know there isn't any high current running to the control box. I can only assume that the trouble was due to either a bad connection there or something inside the controller caused excessive current to flow. It might be good to look inside the controller and look for any clues to the cause.

If the wiring is okay just past the connector then I would splice in the connector from the new harness instead tearing the whole dash apart to install a new harness. It's not ideal but it is way easier.

[CosmoTheCat]

Actually, the blower motor grounds through the resistor then through the fan speed switch and on to GB-12.

Is the bulkhead harness melted, or just the instrument panel harness?

The instrument panel harness is the one that plugs into the switch. It also contains GB12 which grounds on the driver's side down low at the side of the center stack.

[pikker]

Originally Posted by CosmoTheCat

Actually, the blower motor grounds through the resistor then through the fan speed switch and on to GB-12.

Is the bulkhead harness melted, or just the instrument panel harness?

The instrument panel harness is the one that plugs into the switch. It also contains GB12 which grounds on the driver's side down low at the side of the center stack.

Just the connector that goes to the fan speed controller is melted.

Splicing in a new connector and a new switch was the service guys idea as well. (Mine also since I knew this was going to be ugly out of warranty) but I can't find a connector anywhere. The Subaru part is for the entire main harness and they claim they can't get just a portion of it.

[pikker]

[Cougar4]

Thanks to CosmoTheCat for the info about the connection to the motor. The blower motor may have a problem and it is drawing too much current so have it checked out before repairing things. Here is a link to site that may be able to help you. You will need the proper terminals for the connector also.


http://connectors-catalog.sys.yzk.co...list&select=15

Now that I see a picture of the damage I do recall someone else having the same issue.

[pikker]

Before I found this damage I replaced the blower motor, resistor, and blower relay.

I think I've seen someone else have this but it was an older model, I may have seen it in a forrester forum actually.

Thanks for the link. I'll check that.

[Mulder]

It might be possible to just cut the damaged connector off and use individual insulated spade lugs crimped to the wires. However before doing so I'd check the wires in that harness carefully, with damage like that it's possible they are cooked for several inches back into the harness. Any splice or crimp repair should only be attached to wire that is clean, shiny and undamaged.
You might try looking for a wreck in a local junkyard and cutting that section of the harness from it.

[pikker]

Originally Posted by Mulder

You might try looking for a wreck in a local junkyard and cutting that section of the harness from it.

I'm trying. No one has a late model nearby. Spent half the day calling across the country. All these places pull parts but not wires. Frustrating.

[Cougar4]

Originally Posted by pikker

Before I found this damage I replaced the blower motor, resistor, and blower relay.

Well then if the trouble was due to the motor you have obviously eliminated that issue.

[pikker]

I'm assuming this is it. After the dealer inspection today turned up nothing else on a visual inspection.

[Cougar4]

That kind of problem is done by two different ways. Either there was too much current for the connections to handle or the connections were loose and that caused resistance to the connection and the high current across that resistance caused heat to be generated.

[pikker]

well, good news. Subaru USA took my info and contacted the dealer. For any number of reasons, they are going to cover the out of warranty repair. Now I just need to wait for parts to arrive, hoping it won't be too much longer. thanks for everyone's help!

[FirstAidKId]

good to know. 2 grand for that blower motor would've sucked.

[slide]

That's good news!!! It seems they want to know what the heck happened before more cars burn to the ground!

[waltino4]

Originally Posted by pikker

well, good news. Subaru USA took my info and contacted the dealer. For any number of reasons, they are going to cover the out of warranty repair. Now I just need to wait for parts to arrive, hoping it won't be too much longer. thanks for everyone's help!

Did they give you any more information about what went wrong? My 2013 impreza is starting to do some funky things with the blower, and I'd love to avoid this

The fan isn't working on speed 3, but works fine on all other speeds. I changed the Blower Motor Resistor which was a little rusty, but fine otherwise, and it still doesn't work on 3.

When I leave it on 3, then go to 4, there is some weird clicking, but then the fan works normally. I haven't been using 4 just to be safe.

The plug to the blower motor resistor looks fine. I used an OEM replacement too.

Thoughts?

[Cougar4]

In your case I would look for the problem being with the number 3 and 4 positions of the speed switch.

[Charlie-III]

Originally Posted by waltino4

Did they give you any more information about what went wrong? My 2013 impreza is starting to do some funky things with the blower, and I'd love to avoid this

The fan isn't working on speed 3, but works fine on all other speeds. I changed the Blower Motor Resistor which was a little rusty, but fine otherwise, and it still doesn't work on 3.

When I leave it on 3, then go to 4, there is some weird clicking, but then the fan works normally. I haven't been using 4 just to be safe.

The plug to the blower motor resistor looks fine. I used an OEM replacement too.

Thoughts?

Originally Posted by Cougar4

In your case I would look for the problem being with the number 3 and 4 positions of the speed switch.

Agreed.....since ONLY one speed, look to speed control stuff first since it's usually only 2 wires to fan motor......voltage is controlled mostly at the center stack, "maybe" resistor......depends on Year and type of system....

[waltino4]

Originally Posted by Cougar4

In your case I would look for the problem being with the number 3 and 4 positions of the speed switch.

Thanks Cougar4 and Charlie-III. Is there a good way to diagnose this switch before replacing it?

[Cougar4]

The switch usually provides the ground connection to the resistor in series with the motor. The wire color of speed 3 may be yel/blk on the switch. You could check the voltage on the pin while the trouble is occurring. If you see more than a few tenths of a volt on that wire that would indicate a problem within the switch. You could also use a jumper wire between the black wire and that wire while the switch is off and see if the speed works okay that way. If that works okay then the switch is the cause of the trouble.

[waltino4]

Originally Posted by Cougar4

The switch usually provides the ground connection to the resistor in series with the motor. The wire color of speed 3 may be yel/blk on the switch. You could check the voltage on the pin while the trouble is occurring. If you see more than a few tenths of a volt on that wire that would indicate a problem within the switch. You could also use a jumper wire between the black wire and that wire while the switch is off and see if the speed works okay that way. If that works okay then the switch is the cause of the trouble.

Good to know. I will open it up tonight with my multimeter and see what I can do. Thanks!

EDIT: The forecasted rain last night turned into an awesome sunny night so I decided to give the car a wash and detail. Will probably have time next week to dig in. Will update once I check it out.

[waltino4]

Update: I got let out of work early today, and decided to open up the dash and checkout the speed control switch. Didn't even need to break out the multimeter... check it out:

Plug:




Switch:


It looks like I should probably replace the switch (and the plug), unless anyone has a different idea.

Also, does anyone think I need to worry about this happening again if I replace the switch? I am keeping the new blower motor resistor in since it wasn't too expensive. Other things I should make sure aren't bad?

[Cougar4]

The problem could due to a couple of things. My first suspicion would be the connector itself was loose and that caused the heating issue. The other possibility is the motor is drawing too much current so that needs to be checked out. You can monitor the current at the fuse position. You will need to either replace both ends of that connection or you could bypass that wire connection with new terminals on each end. That will require some modification but may be easier and less expensive than replacing the OEM connectors. This is a pretty common issue.

[908VAL]

I agree with Cougar 4, just cut connector out of circuit. Process of elimination you just eliminated the connector