[BangBang]

*update* I ordered and installed the lock assembly and that did not fix the problem. Took it to the dealer today and they said it's a bad body control module (BCM). Quoted $900 for diag, part, labor, and programming. =(

Hi Jctek,
Your problem sounds identical to mine (i have a 2010 model 6). I am curious if changing the BCM fixed the problem.
Yikes I bought a Mazda as everyone told me they rarely get problems. Hmm thinking I should have got another Ford..

Cheers
Drew

 

[kms1990]

Hi Jctek,
Your problem sounds identical to mine (i have a 2010 model 6). I am curious if changing the BCM fixed the problem.
Yikes I bought a Mazda as everyone told me they rarely get problems. Hmm thinking I should have got another Ford..

Cheers
Drew

your 2010 mazda 6 is more ford then you realize. look under the hoos what do your spark plugs say? fomoco what do your motor mounts say? fomoco a lot of many mazdas where ford products until very recently. bcm or wiring short is worse possible scenario here. it could be as simple as a stuck sensor, they have a little tab that locks in and tells the car door shut or door open check inside the latch on each door you should see them and push each one and if one sticks that's your issue, and mazdas are actually very good cars I have had many throughout the family and personally and all have been pretty good.

 

[Natureboy]

Hey guys, I'm having a problem with my 2010 mazda3 hatchback. While driving, occasionally the "door ajar" light turns randomly on and off and according to the display, the faulty door is the front passenger door. My question is where in the door can the problem lie? There is no button on the door that comes into contact with the body so I'm guessing the sensor is part of the entire lock assembly. It happens so randomly that I have to leave the center dome light permanently off as it has turned on in the middle of the night before due to the car suddenly thinking the door is open. What do you guys think? Any help will be greatly appreciated as it is no longer under warranty so I will have to purchase/install any parts by myself.

Hi while your query was some years ago, but I thought I should still respond as I had the same problem just recently. I found a solution on Youtube which suggests to spray lubricant on all your door hinges and door latches. I used WD40 and it seems to have stopped the problem. Hope this helps.

 

[neemoxtrm]

I've for years had the exact same issue as OP, even down to the problem being much worse in warmer weather. A bunch of WD40 in the door hinges/latches did indeed fix it.

 

[Tylerhugg]

I have a 2014 mazda3 my Interior lights dont turn on when I open the doors. Is there a button to turn the sensor on/off or could this be a wiring problem?

 

[rlwmmw]

[Solved] I know this is an old thread, but I had the same issue, and it was draining the battery (even with the dome light turned off). All troubleshooting of the battery drain issue pointed to the door ajar sensor problem.

I tried WD-40, but it didn't solve the problem. I ended up taking the driver and passenger side door panels off (3 screws - 2 under the handle cover and 1 behind the door latch. The rest are the plastic pop-in kind, and I had to replace most of them).

The sensors, which is part of the door latch/lock mechanism have a wiring harness with 2 pins. At least there are 2 pins on mine, which has manual locks. I sprayed the pins and the harness with dielectric cleaner spray (CRC 5103 Quick Dry Electronic Cleaner), reconnected them, and made sure they were well seated. That appears to have done the trick. No more door slamming, and hopefully, it solves the battery drain problem as well.

 

[MinimumJargon]

I was having the OP's issue along with my alarm going off with it was locked. dome lights would come on and door ajar would flicker on and off while driving.
Here's what solved the issue for me.
Easy repair. Just basic tools and a couple of hours.

These use a sweeper arm, kind of like a fuel level sensor in a fuel tank, to tell if the door is open or closed.
Over time these arms can wear down a bit or get jostled hard enough to bend the arm, making good contact hard.
The doors use: circuit not grounded = door open
circuit grounded = door closed

-Remove the door panel
-Unplugged everything
-Unbolt door plate and let hang, no need to remove
-Remove plate
-Undo the 3 screws for the latch assembly
-Undo actuator rods for handle and key
-Pull unit out
-Remove screws and open unit up(It is not glued together)
-Remove the arm and bend brushes out slightly
-Reassemble

Hope this helps someone

 

[Yoshimail]

I was having the OP's issue along with my alarm going off with it was locked. dome lights would come on and door ajar would flicker on and off while driving.
Here's what solved the issue for me.
Easy repair. Just basic tools and a couple of hours.

These use a sweeper arm, kind of like a fuel level sensor in a fuel tank, to tell if the door is open or closed.
Over time these arms can wear down a bit or get jostled hard enough to bend the arm, making good contact hard.
The doors use: circuit not grounded = door open
circuit grounded = door closed

-Remove the door panel
-Unplugged everything
-Unbolt door plate and let hang, no need to remove
-Remove plate
-Undo the 3 screws for the latch assembly
-Undo actuator rods for handle and key
-Pull unit out
-Remove screws and open unit up(It is not glued together)
-Remove the arm and bend brushes out slightly
-Reassemble

Hope this helps someone

How is your repair holding up? I just got the car on September and My BCM thinks my doors are open sometimes when I corner hard, more times on the driver's side but sometimes the passenger side will turn on and my alarm will go off on its own sometimes as well. I'm replacing speakers in the front so I might Tackle these at the same time.

 

[MinimumJargon]

How is your repair holding up? I just got the car on September and My BCM thinks my doors are open sometimes when I corner hard, more times on the driver's side but sometimes the passenger side will turn on and my alarm will go off on its own sometimes as well. I'm replacing speakers in the front so I might Tackle these at the same time.

Repair is still working with zero issues. No door ajar, No alarm going off and No battery drain.

Just be careful opening the unit and you shouldn't have an issue.

 

[ayavilevich]

I was having the OP's issue along with my alarm going off with it was locked. dome lights would come on and door ajar would flicker on and off while driving.
Here's what solved the issue for me.
Easy repair. Just basic tools and a couple of hours.

These use a sweeper arm, kind of like a fuel level sensor in a fuel tank, to tell if the door is open or closed.
Over time these arms can wear down a bit or get jostled hard enough to bend the arm, making good contact hard.
The doors use: circuit not grounded = door open
circuit grounded = door closed

-Remove the door panel
-Unplugged everything
-Unbolt door plate and let hang, no need to remove
-Remove plate
-Undo the 3 screws for the latch assembly
-Undo actuator rods for handle and key
-Pull unit out
-Remove screws and open unit up(It is not glued together)
-Remove the arm and bend brushes out slightly
-Reassemble

Hope this helps someone

Thanks for the detailed guide.
Before the fix, was it always the same door that was giving the "door open" signal or was it happening to various doors? I have a similar issue but it happens with different doors. At least 3. Trying to understand if the fix could be relevant.

 

[MinimumJargon]

Thanks for the detailed guide.
Before the fix, was it always the same door that was giving the "door open" signal or was it happening to various doors? I have a similar issue but it happens with different doors. At least 3. Trying to understand if the fix could be relevant.

Each door has one one these. It very well could be happening to all 3 doors. Usually it's the drivers door due to how often it get use.

What I would recommend is trying the fix on the drivers door and then monitor it for a couple days and see if that door no longer shows open. If so then I would repeat it on the other doors. If it still shows up as one of the doors showing open you probably have a different issue.

 

[thierryble]

Hello, just sharing my experience here and it was nice to read all yours too! Thanks, it helped a lot.

I am having this problem too since a year and a half. It was draining my battery so I had to change it and remove the Room 15A fuse and for the first 2-3 weeks, the light did stop to show. Hmm. But then it would appear sometimes when I was accelerating or stopping or both, whatever, it stayed on solid after few days. Probably a loose wire somewhere...

I opened all door interior, latches/actuators, 1 by 1 probably for nothing because when I click the un/lock switch on both driver and passenger doors, every latches work just fine. They unlock and they lock! Could a latch be working but shorted?
Therefore, on the remote, the unlock button is working but NOT the lock button. <- wait, waaaat? Yes.

Anyway, when I would leave the key in the ignition, it would beep when I'd open any door and stop beeping when the door was closed. So the light was on no matter what but the computer was understanding that the doors are working properly which brings me to a what the heck moment lol So I went to the mechanic, they bypassed all 4 doors and the dash light was still on which confirms the electrical problem and not a door latch (for me).

They said the BCM was faulty (which is not buyable separatly because it is soldered into the PJB (Passenger Junction Box). So I found one at a scrap yard for 100$, swapped it and the dang light was still on! I then tried another PJB and same thing. Were the three BCM/PJB faulty? I don't think so.. so then I decided to unplugged each J-series connectors from the PJB and see if the light goes off and guess what... the light went off when I disconnected the J-04 connector! Now I just need to understand how I can check which of the wire is grounded or open circuit or I don't know how to call it, either how to measure it because I don't know where is this J-04 connector comming from or going to lol. Maybe it does go to the famous BCM and then okay, the three BCM were faulty so now I'm on the J-04 connector!

 

[ayavilevich]

Thanks again MinimumJargon for the guide. Since finding this thread I replaced both left and right front latch units. Having some rare issues with the back right unit now but so far not planning to replace it.

The symptoms I experienced: Car thinking the door is open when it is not. Not being able to lock the door electronically while the key was working fine. I suspect these are separate issues (lock motor vs sensor wiper) but symptoms were most likely to happen if the car was hot (parked in the sun during summer) rather than cool.

Initially I took one of the units out and tried to "repair" it. My unit was glued so it was an effort to take it apart. Cleaning and bending the wipers made it work better but didn't resolve the issues completely. I got to new lock units (150$+ each) and done the swap.

Some additional tips:

When opening/removing the plate, don't unscrew the bottom nut for the window rail. it will be very hard to put it back. Also, don't close the window all the way up to reduce any stress on the parts, leave a small gap. I removed all screws around the perimeter of the plate except the two that are close to door hinges.

Use a "Manual Impact Driver" to open the 3 screws for the latch.

The lock is connected to the door key-hole by a mechanical arm. What I have done to release it was to push on a plastic part with my finger through a small hole in the side of the door. The hole has a plastic "cap" that covers it normally. The hole is above the 3 screws that bolt the lock to the door. Use your finger to push on the plastic clip that holds two metal arms together. Push on the bigger side of the clip (more leverage). Remove the lock with the short arm and then transfer the arm to a new lock before reassembly.

The lock is connected to the door handle by another mechanical arm, but this one has no plastic clip. The rod from the handle just goes in to a hole on the unit. It is easy to take a part or assemble together.

The new lock units solved my issues and all is working correctly for some time now.

I also used the following video guides which you may find useful if you want to try this yourself:

 

[Slu]

Hi All

First post here, dug this up while trying to find the answer to the same issue (drivers door saying open, interior lights coming on - currently switched off to save battery, alarm going off etc).

I ran throuhg the above all the way to getting the 3 screws out the actuator, and was trying to remove the handle rod - but on mine (2010 mk2 Mazda 3 sport, with keyless etc) removing those 3 screws does not let me manuver the actuator to release the rod.

It feels like there is something else holding it in place (I believe there is a second rod for the key but I cannot see this), and I have some additional plate work blocking access and view. Looking at the service manual (found a copy here: https://www.allcarmanuals.com/factory-service-manual-346-Mazda-3-BL.html ) - it seems you should remove a bolt through the service hole above (which I assume releases the metal plate work), can anyone confirm how they managed to get through this?

Actually reading back the points above, it does suggest remove plate - so I presume that is the case of removing the bolt through service hole referenced in the manual?

 

[slovell]

Like many others, my wife's 2011 3s Hatchback is intermittently showing the front passenger ajar when it's closed and turning on the interior lights draining the battery. I've been reading this thread with a lot of interest but has anyone come up with a definite fix for this? I don't want to just swapping out parts hoping I'll hit on something. I tried spraying the locking mechanism with WD-40 but it didn't seem to help.
Thanks

 

[Slu]

Like many others, my wife's 2011 3s Hatchback is intermittently showing the front passenger ajar when it's closed and turning on the interior lights draining the battery. I've been reading this thread with a lot of interest but has anyone come up with a definite fix for this? I don't want to just swapping out parts hoping I'll hit on something. I tried spraying the locking mechanism with WD-40 but it didn't seem to help.
Thanks

Off the back of my previous query, mine is now fixed (at least so far, been a week and not a single reoccuramce yet).

I tried the wd40, won't help as the unit is sealed (providing it's the same issue as above). Only way I could fix it was to get the latch out as described above, and clean/bend out those wings that identify the door open/shut.

It's not for the feint of heart, but manageable with patience.. difficult bit is removing the latch when you cannot see what you are doing (to answer my own question above, the plate blocking me needed removing to get to the second set of rods, it's bolted in and has a plastic clip at bottom that comes out with encouragment).

Happy to help if you go down the route of trying it and have questions.

 

[slovell]

Thanks much for the reply and advice. I've installed many modded door speakers and a few window regulators in my day so I'm not afraid of taking the door innards apart. Would it be easier to just buy another used/working latch mechanism and go from there or just try to repair the one that's in it? I stopped the battery drain by turning off the interior lights but I really don't like my wife having to get into a dark car at night. It's finally cooled off enough here in SC that I can start working in my garage without getting a heat stroke lol so it's time to fix it.

 

[Slu]

Well,. The difficult bit is getting the unit out so if it were me I would just try and fix the existing unit (once it's out the door, cracking. It open is pretty simple although unlike others mine was glued so required some encouragment with a screwdriver).

 

[antoninomubarik]

sometimes that type of problem is impossible to locate, and some folks have paid a fortune in labor costs tracking something like this down.

snaptube vidmate​

 

[Spitfire-666]

Same problem here. I have satnav in my 2010 BL that shows which door is "open".

When driving, the "Door Open" alert randomly happens. It's just the front doors.

This has flattened the battery a few times overnight. I'll see if the suggestions in this thread fix it 🤞