Trunk won't open and doors won't lock/unlock

[Mazikowski]

So yeah, my trunk won't open electronically. I checked the cancel button and it's in the correct position (I actually checked it both ways just to be sure).

EDIT:
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Also, the door locks won't actuate (fob or button on door panel). These problems seem to be connected, but the only thing I can see they have in common is the D/L relay and the Main Body ECU itself.
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Looking at the shop manual, I have checked the only fuse (labeled D/L in the engine bay) that appears to be directly related to the trunk opener and it's fine.

According to the manual (see the attached picture), the connector pins out like this:

B:   Ground
W-B: TSW5 pin (trunk open/closed switch) from the Main Body ECU
BR:  Latch trigger (normally grounded by the BK/DR relay, switched to 12v to open the latch)

The pins all checked out except when I tried to open the trunk, via the key fob or the button above the license plate, the latch trigger was never switched to 12v.

I removed, tested, and broke (turns out the little motor in the opener doesn't like 18v and I let the magic smoke out) the latch opener and it unlocked just fine (before it broke). No worries, though... I got a new one coming from a part-out.

This leads me to think maybe the relay went out but it appears that the relay is actually inside the Main Body ECU.

Anybody have other ideas of stuff I should check?

[Brayden_23]

Possibly an issue with your FOB?

[Mazikowski]

Originally Posted by Brayden_23

Possibly an issue with your FOB?

That was my original thought but when I hold the button on the fob it still beeps. It won't open with the button on the dash, either.

[Sapphireho]

Originally Posted by Mazikowski

That was my original thought but when I hold the button on the fob it still beeps. It won't open with the button on the dash, either.

Maybe the disable button in the trunk got damaged?

[Mazikowski]

Originally Posted by Sapphireho

Maybe the disable button in the trunk got damaged?

You know, I hadn't thought about that... and I remember reading a post that said if you remove the button it's the same as putting it in the cancel position (I guess it allows the trunk to open when that pin is grounded)...

I'll have to pop it out when I get home and test it. I'd much rather fix/replace it (or just permanently bypass it) than have to replace something more expensive.

[Chimera]

Originally Posted by Mazikowski

You know, I hadn't thought about that... and I remember reading a post that said if you remove the button it's the same as putting it in the cancel position (I guess it allows the trunk to open when that pin is grounded)...

I'll have to pop it out when I get home and test it. I'd much rather fix/replace it (or just permanently bypass it) than have to replace something more expensive.

I'm taking a wild guess but maybe there's a motor that actually is supposed to release the trunk that's not working?
If you get the beep, maybe try opening the trunk with the key, then use the fob to "open" it and try to listen over the beep for movement... or lack of movement?


Is it a brz with the cover over the back of the trunk, maybe pull the push rivets for that and look to see if anything is obviously amiss?

[Mazikowski]

Originally Posted by Chimera

I'm taking a wild guess but maybe there's a motor that actually is supposed to release the trunk that's not working?
If you get the beep, maybe try opening the trunk with the key, then use the fob to "open" it and try to listen over the beep for movement... or lack of movement?

I did just that. I opened the trunk with the key, closed the latch, and tried unlocking it with the fob, the trunk button, and the dash button. Not a sound.

Like I said in my original post, I tested the opener by itself and it worked (and then broke because my dumb ass used an 18v battery to test it, burning out the motor).

[Tcoat]

Originally Posted by Mazikowski

This leads me to think maybe the relay went out but it appears that the relay is actually inside the Main Body ECU.

Anybody have other ideas of stuff I should check?

Hate to sound like an IT guy but have you tried disconnecting the battery to reset the BCU?

[Mazikowski]

Originally Posted by Tcoat

Hate to sound like an IT guy but have you tried disconnecting the battery to reset the BCU?

As an IT guy myself, I honestly hadn't thought of that.

[Bach415]

Have you checked whether or not that button in the trunk is still connected? At one point, I disconnected that plug to it just to see what would happen and it still gave me the sound but it didn't pop open the trunk both the fob and in-cabin.

[toast]

This. The tab that holds the plug in place in the back of the button is tiny and it doesn't take much for it to come out. I pulled out my interior pieces one time and forgot to disconnect it; I barely felt it yank out.

[Mazikowski]

Disconnected the battery for probably half an hour and no change.

Trunk switch didn't come unhooked.

While washing my car I also found out the door locks aren't actuating, either. The only ly common elements I can find between them and the trunk is the D/L fuse and the Main Body ECU.

Sent from my SAMSUNG-SM-G930A using Tapatalk

[Mazikowski]

TLDR: D/L fuse in the wrong slot. Also, I hate myself right now.

Took the car to Subaru last week (I have a friend who's a tech in the service department) to have this looked at. He checked the body ECU and found some old fault codes from when I had to have the battery replaced, but nothing related to the problem at hand.

After about an hour of hunting he sends me a text saying it's fixed. He says "Yeah, your door lock fuse was just missing." Apparently when I first had the issue and checked the fuse I put it back in the wrong slot (an empty one two down from where it should have gone). Effectively I paid $90 for him to move a fuse. He cut me a deal on his labor because he felt bad for me...

Still no idea exactly what caused the problem to begin with, but my working theory is that while I had the car in the garage tinkering with it I left the keys on my workbench which is within range of one of the exterior keyless antennas and that battery saving feature where the car and the fob stop talking after about 10 minutes kicked in.

I didn't have the doors locked at the time, so I didn't realize it and the only way to reset it is to manually unlock the DRIVER SIDE DOOR with the key. Opening the trunk with the key doesn't cut it. So I checked the fuse and since I put it back in the wrong place I noticed the doors wouldn't unlock even after resetting and it sent me down this long road of unnecessary troubleshooting.

[Tcoat]

Originally Posted by Mazikowski

TLDR: D/L fuse in the wrong slot. Also, I hate myself right now.

Took the car to Subaru last week (I have a friend who's a tech in the service department) to have this looked at. He checked the body ECU and found some old fault codes from when I had to have the battery replaced, but nothing related to the problem at hand.

After about an hour of hunting he sends me a text saying it's fixed. He says "Yeah, your door lock fuse was just missing." Apparently when I first had the issue and checked the fuse I put it back in the wrong slot (an empty one two down from where it should have gone). Effectively I paid $90 for him to move a fuse. He cut me a deal on his labor because he felt bad for me...

Still no idea exactly what caused the problem to begin with, but my working theory is that while I had the car in the garage tinkering with it I left the keys on my workbench which is within range of one of the exterior keyless antennas and that battery saving feature where the car and the fob stop talking after about 10 minutes kicked in.

I didn't have the doors locked at the time, so I didn't realize it and the only way to reset it is to manually unlock the DRIVER SIDE DOOR with the key. Opening the trunk with the key doesn't cut it. So I checked the fuse and since I put it back in the wrong place I noticed the doors wouldn't unlock even after resetting and it sent me down this long road of unnecessary troubleshooting.

LOL. Anybody that says they haven't done something similar is either lying, have only had a car a short time or have selective memories.


If the fuse had been in the right spot then the battery reset would have worked.