Car is unlocking

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Philo
Posts: 2166
Joined: Feb 12, 2006 12:00 PM
Location: Long Beach, CA

Car is unlocking

Post by Philo »

I've got a central locking issue and need a refresh on the systems operation.

So when I lock the car the system locks and then unlocks. I try again and the same thing happens, eventually the car locks. Several times I'll come back in the morning with the car unlocked.

I did notice that the drivers side lock isn't turning smoothly and wondering if this is the cause.

Watchable think ?
Mike W.
Posts: 26872
Joined: Feb 12, 2006 12:00 PM
Location: California Whine Country

Re: Car is unlocking

Post by Mike W. »

Someone may have a better answer, but I had a vaguely similar thing happen.

I don't recall if the key was hard to turn, but the whole thing was acting oddly. Sometimes I couldn't lock it, sometimes it didn't want to unlock, I was worried about not being able to get in. It turned out to be a mechanical problem. In the latch assembly, #1 in the image, there was a broken hairpin spring. One of those two loops with an arm going one way and something else going another. It was causing binding or something, this was back in '99 so the memory isn't crystal clear. So depending on which way it was out of position, it would make it do one thing or the other. Sometimes I'd lock it and it would unlock. Other times I'd unlock it and it would relock. Again and again. Drove me nuts for a time. I found a replacement spring on an E12 latch assy I just happened to have laying around. May or may not be your problem. Hmm, just noticed, it says only until 4-85 and mine was a 1-85 production date. I don't know how much different it would be.

https://www.realoem.com/bmw/enUS/showpa ... Id=41_0566

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Galahad
Posts: 496
Joined: Sep 06, 2016 9:08 PM
Location: Beverly/Worcester, MA
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Re: Car is unlocking

Post by Galahad »

my car will sometimes unlock itself after locking, I have a fob. Not sure what's actually going on, but it's somehow tripping the "unlock" signal by itself.
LarryM
Posts: 1222
Joined: Feb 01, 2008 11:40 AM
Location: SoCal

Re: Car is unlocking

Post by LarryM »

I had the same issue with mine. I discovered and re-soldered a broken solder connection in the central locking unit and that worked for awhile, but it eventually failed again. I decided to purchase a remanufactured unit from ProgRama and it's been working fine for years.
Zeta
Posts: 153
Joined: Sep 07, 2017 12:33 PM
Location: Salt Lake City

Re: Car is unlocking

Post by Zeta »

Be careful! I had this exact same issue, including the driver’s side lock being hard to turn, but I didn’t do anything about it, and eventually the driver’s side lock straight up broke. I haven’t replaced the lock yet because I can’t afford to, so I’ve been locking and unlocking the car from the trunk or passenger side, and I haven’t had the unlocking problem since then. So I conclude it must have been a mechanical issue with the driver’s side lock, but I don’t know specifically what it is.
jhh925
Posts: 913
Joined: Jul 11, 2015 12:23 AM
Location: Reno

Re: Car is unlocking

Post by jhh925 »

Philo wrote: May 27, 2023 5:31 PM So when I lock the car the system locks and then unlocks. I try again and the same thing happens, eventually the car locks. Several times I'll come back in the morning with the car unlocked.

I did notice that the drivers side lock isn't turning smoothly and wondering if this is the cause.
I had this exact same thing happen. In my case, the driver's door central locking actuator was bad and had to be replaced. One of the motors in one of your actuators is likely bad in such a way that when it gets the "lock" signal, the motor isn't able to pull the plunger down, so that this bad actuator is essentially immediately delivering an "unlock" signal to the system.

To test this, pop the door card off of the door you're testing, and see if that causes the 'unlocking' problem to go away.

Also, note that various doors have different codes painted on them in white, e.g., depending on whether you have the deadbolt feature or not, the driver's door actuator is marked FT on it (w/ deadbolt) or TV (w/o deadbolt). See Bentley, ch 20, pg 19.
Blue Shadow
Posts: 10195
Joined: Feb 12, 2006 12:00 PM
Location: SE PA

Re: Car is unlocking

Post by Blue Shadow »

That sounds like a possible cause, since it can be occasional as the U soldered tab in the CLCU would be an everytime unlock signal. That is a safety feature for auto unlock when the car ends up not on its feet, the doors automatically unlock.


Who uses the driver's side lock anymore?

The microswitch for the deadbolt actuation is the only reason I would use the driver's door lock. It is rarely needed. Not using it saves the wear and tear and rearrangement of the parts that lead to broken parts and failure. Most have installed remotes, but I just use the trunk lock to lock and unlock the car.
LarryM
Posts: 1222
Joined: Feb 01, 2008 11:40 AM
Location: SoCal

Re: Car is unlocking

Post by LarryM »

Blue Shadow wrote: Jun 01, 2023 1:18 AM ....I just use the trunk lock to lock and unlock the car.

Ditto! The trunk lock gives me the impression it's more ruggedly built than the door lock mechanisms, and would probably be easier to change if that ever became necessary.
ahab
Posts: 6174
Joined: Jun 11, 2006 9:12 AM
Location: Chalfont, PA

Re: Car is unlocking

Post by ahab »

Too add some insight here, I experience the same thing from time to time using that old Viking or Vulcan (or whatever we all used to buy), remote fob thing. I press the button and everything locks then within a half second everything unlocks. If you've ever locked your doors with a door open and noticed that they automatically unlock again, I accidentally found out that the driver's rear door is "locking" in the sense that the plunger/lock pull goes down, but I can still open the door from the outside. When I lift the handle it makes a weird clunk noise and then opens. My theory is that there's enough resistance against the lock motor that it's not actually completing the lock cycle every time and sometimes they all auto-unlock when I press the button, sometimes they don't, but I can almost always still open the driver's rear door despite it appearing locked (please don't tell anyone).
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