cincy8

Does anyone else have this problem where you open the door and the alarm rings? It almost as if the alarm doesn't get the message that I have the key but the door unlocks. I tried changing the battery.

Usually, the alarm does a couple of quick rings but twice it stayed on and I have to fish the key out of my bag to stop it.
This doesn't happen all the time, but seems to be more frequent.

docfnky

Do you have the soft closing doors? Might be a latch that's gone bad. I had this happened to my 550. All doors would lock except for 1 due to a bad latch. Whenever I opened that door first the alarm would go off. I'd check to make sure that all doors are locked by opening the doors without the keys nearby.

asm777

Are you sure the door was locked in the first place? We had a door lock go bad on a passenger front door. Alarm would keep going off because passenger opened unlocked door (while car was "locked" and alarmed) before driver got close enough to disarm. Finally figured it out and dealer replaced the locking hardware under warranty.

cincy8

Thanks for the tips.
You've helped me in knowing what to look for... this happens when I lock the car from the back driver passenger door, and later open from the driver's door.
So it could be one of these issues.

snowflakeGL

Its funny i read this thread a couple of weeks ago, and last weekend the same occurred to my 13' GL550. Anyone with out the key fob could open the drives side rear passenger door and set the alarm off. I tried it 3 times in a row without the key fob and it never locked or stayed locked. I dropped it off the dealership yesterday, and the Service manager mentioned that the "door lock actuator" parts have been ordered and they will fix it. I'll post the service ticket up when i pick it up tomorrow. Thank god it still under warranty.

Richrpilot

Id like to see the repair parts ticket since my 2014 has a similar problem

cincy8

Mine goes in tomorrow.

Richrpilot

Mine too. Snowflake??

snowflakeGL

I don't have the paperwork with me right now, but from what i remembered the part they replaced was the "door lock mechanism" dealer price was around 175.00 for the part only + labor. This was for rear drivers side door.

I'll scan and post once when i get home from work today.

Mine was replaced under warranty. a few month's ago it was the soft close mechanism on the rear passenger side that failed, allowing the door to open on its own. I've owned a few other Benz's in the past without any issues, but these x166's are already starting to look like a bad build.

Richrpilot

Thanks. I have 36 months of warranty to decide if this one is a keeper.

snowflakeGL

Sorry Guys/Gals, i completely forget about uploading the service ticket. I have texted my service adviser to see if he can email it to me but he hasn't responded yet.

wamochi

same thing happening on my 2013 550.

for months i thought it was my son doing something weird. he sits in the seat behind driver, and he would walk up to car and try to open his door and set off alarm each time. then i'd have to run closer to car to disarm.

we finally remembered to run a test yesterday and try every single door and trunk to make sure it was locked. once i got to that driver side rear door, sure enough it opened and alarm went off.

my warranty just ran out in May 2017 but we only have about 26k miles on the car so i'm hoping they will do a goodwill repair on this.

thaiedwin

Hi my GL450 2013 had the same issue, I just got it under cpo and the dealer is replacing the whole door module, but a trick to lock the door is to push the door pin down before closing the door. That way the door will stay locked

wamochi

thank you! that would explain that when i took it to dealer they could not replicate. the night before i was fiddling with the lock pin and that must have "fixed" it temporarily.

for now, they are replacing the lock module as i can't risk the door being accessible and having valuables in the car.

Dog hauler

My 2014 GL350 did that a couple of times. I don't recall the circumstances under which it happened, but I locked the doors after parking. When I returned to the car with key in pocket, the driver door opened but it set the alarm off.

I have soft close doors, but they seem to be working fine and I never got a door open warning on the dash while driving. The problem only occurred twice and hasn't happened for quite some time now. I haven't bothered to go to the dealer with the issue because they'll no doubt tell me that if it doesn't happen right there in the service department, there's nothing they can do about it.

thaiedwin

the door module is controlled by the AAM using SDS they can read the code for the door module, if you got such issues they will be able to pick it up. Even better if you go to the service and diagnosis it with them, as that is what I did

Lawrence Lane

We had this same issue. Turns out the rear doors were never locked which was why the alarm would go off sometimes (when the key isnt detected by the time you pull the door). They did a software update, didnt work, then ended up replacing all door lock components. Fixed it.

cincy8

Lawrence Lane

This is basically what they had to do since the rear doors weren't actually locking (even though the door appeared locked).

cincy8

Thanks! So can you explain the scenario that resulted in the alarm going off? Was it repeatable? Only when you opened specific doors? I haven't figured that out.
I have soft close doors and I know the last time they did fix that - but I don't know if it was a specific door or all. (I wish we had electronic documents) For a couple of months we didn't have the issue, now we do.

thaiedwin

mtm

I had these symptoms - locked doors opening and alarm going off. The dealer ended up replacing door lock actuators on passenger side front and rear doors.

Additionally, after picking up the car, I noticed that in these two doors the soft close mechanism was now engaging even if the door was properly closed. On the other two doors, unless the door was not fully closed, the soft close mechanism didn't engage. Turns out that the new door lock actuators are programmed from the factory to always engage the soft close mechanism. The dealer was instructed by MB USA to update the firmware on the old parts in my other two doors to do the same.

Lawrence Lane

1. Press the lock button on the remote to arm and lock the car. Put keys at a distance from the car far enough where it won't allow you to unlock the doors by touch.
2. Go to each door, pull on the handle. If it opens, and the alarm goes off, then its not locking.
3. Repeat for each door to determine which ones are defective.

We had problems on the rear two doors, and our dealership also updated software for the remaining doors (fronts).

cincy8

After 4 attempts at a repair I'm still having alarm problems. It's funny how an annoying problem can totally change your attitude to the car that I used to love.

I soft close the drivers door. Lock with the fob. Walk the fob away. Pull on the door and alarm goes, door opens. Yet, I couldn't reproduce it at the dealer. I can at home. It happened for a week when doing college visits with my daughter - she drove, I had key as passenger. It seemed half the time she pulled the handle without the key, the alarm went off.

I have had actuators replaced in one of the earlier attempts. I'm wondering now if it has something to do with the programming as MTM states.