mbglc321

Has anyone else had the issue where the SUV will lock the keys inside?
I thought that this was impossible to do with a car now a days.
My 2017 Honda CRV, 2017 RAM 1500 nor my 2020 Toyota Highlander, let me lock the keys inside the car, but my brand new Mercedes does?

superswiss

What was the scenario? There are indeed ways you can lock the key inside. For example if you unlock it and don't open the front door within 30 seconds it will auto-lock itself. Some people have managed to get their keys locked in that way by only opening a rear door and putting their bag inside and then before they could open the front door the car locked itself again. Not sure if this is still an issue in the latest cars, but it appears you have to open a front door within 30 seconds to avoid the auto-lock.

Also, in response to the relay attacks, the fobs now have a motion sensor in them and if no motion is detected for about 2 minutes the fob stops sending out a signal, which means it's no longer detected by the car. You shouldn't be able to lock the car in that situation, either, unless the second key is on your person and then it would lock in the dormant key.

There's one more possibility for locking in your key. If you only unlock the trunk and throw the key in and then shut the trunk, it's possible that the car doesn't detect the key if the signal is shielded by something in your trunk or the battery is weak, or as mentioned above the key fob hasn't sensed motion for 2 minutes and went to sleep.

pussgalore

One time I put my purse with the key inside in the trunk while loading gardening supplies, closed the tailgate and opened the driver door and the alarm went off in the undercover parking and everyone around me got startled.

mbglc321

Mainly, when I turn off the engine, get out of the car and lock it using the door handle with the key inside.
None of my other cars will let me do that, they will sound the horn and unlock the doors.
The MB let me lock the keys inside that way.

decorily

Does it unlock again if you press the button on handle ?

superswiss

Yeah, that's not how it's supposed to work. FWIW, I just double-checked on my C63. If the key is inside and I try to lock, nothing happens. It won't allow locking the car no matter how often I touch the door handle to lock. The fob has to be outside on my person in order to lock, and I know from experience that if I lock the key in the trunk it immediately pops open again.

Where in the car is your key at the time? If it's close to the door, then it could lock the car, but should also unlock again. The system is not as precise if the key is near the car's boundaries. For example I cannot start the engine if the key is on the roof, but if it's on the pano roof then it works. There are multiple antennas in and around the car that triangulate where the key is. The way it should work is that you can only lock/unlock if the key is outside and near the door handle you are using. Similarly, the kick to open for the trunk only works if the fob is near the trunk.

Have you tried a fresh battery? When you turn off the engine and open the door, does it say "Don't forget the key inside" or something like that in the instrument cluster, and are you sure there's on other key nearby?

dalazernet

I just did this the other day… opened the trunk, put my bags and keys in the car, shut the trunk (being careful to only press close and not lock of course)…. But not realizing I hadn’t unlocked the car at all yet. There in what seemed like slow motion I watched the hatch close in on my keys.

luckily I had my phone on me still so I unlocked from the app. But yeah, won’t do that again.

pussgalore

I tried to lock the door by touching the door handle being unaware that I left the key inside the center console and it didn’t lock the door.