The new keys used with the 213 are different (in appearance and functionality) than those of the 212. The key used with the 213 has an accelerometer that after a few minutes of inactivity, even inside the car, stops the signal broadcast. This is, in part, to help prevent relay signal stealing of cars.

 

Nothing new with the W213. Any W212 (with Keyless Go) uses the same accelerometer technology, regardless of key appearance.

As you observe, enterprising car thiefs now use electronic devices to detect smart keys 1) outside a parked car, but 2) still within range of the car. Just enter car and use the device as a relay, press keyless go and they are gone without the key present (because the key is within range and still communicating with the car). If the smart key were deactivated via the accelerometer, then the key would not be detectible, and could NOT be used to start the car. This confirms that the key remains active unless it is taken out of range and allowed to sit still, then power down.

The logic within the key (or car system) assumes (first, by default) that a key within range is there to be used to start the car, so it remains active. Take it out of range, then the secondary shutdown logic takes over. Makes perfect sense.

Someone posted this surveillance cam video of a relay device theft of a Keyless GO MB in action in the UK.

NOTE: The MB is a current model E or C... Looks like a W213 to me.

The thief is at the garage door scanning for the (still active) key, and finds one, because it is still within range of the car and alive, even though the key is sitting perfectly still. As you suggest, the accelerometer should have turned the key off, but hasn't, because the car is still within range and maintains a handshake with the car.

If the key were truly powered off (stored further away in the house where the accelerometer would then work), then the cretin would not have detected the key. So much for accelerometers saving the day...


This has all been verified by Konigstiger in previous discussions,
like this one... https://mbworld.org/forums/e-class-w...y-warning.html
Or this one on this forum....https://mbworld.org/forums/e-class-w...e-vehicle.html
And another...https://mbworld.org/forums/e-class-w...ss-remote.html

 

wow that's surprising that MB would override the key ant-theft feature based on proximity to the car (especially since this was added specifically to address the radio amplification attack you showed on video). They shouldn't need the key powered on after you've started the car, but even if they did, for some reason, the movement of the vehicle should still ensure the key detected motion and stayed active on its own.

 

Just looked at a 2019 E450 Wagon at a dealership today, and asked about the mirrors. They said, and I confirmed, they can be manually folded out of the way. Good to know for sure. While I intend to fold mine when locking (good indication of car being locked), might not do it in the garage, and if I need to squeeze by, I'll know I can rotate them manually, without having to get the key.

I assume that left folded, they will come back out by themselves when the car is started? (Couldn't do that at the dealer - it was inside.)

 

I don't know if there is a difference between European and US versions but this is definitely not the case with my keys. In Europe MB introduced motion sensors in the E-class keys with keyless entry at the start of modelyear 2019. I have tested this with my keys by letting them lie still next to the car. After a few minutes I can not open my car by touching the door handles although the keys are right next to it. I'm pretty sure the key also switches off when it is placed inside the car because my wife several times could not lock the car after a ride by touching the door handles because apparently she moved out of the car too gently with the key in her bag. The car only needs the key to start but once running it does not need the keysignal anymore.

I have learned that the key does not send a signal constantly but the car "wakes" the key by sending a signal to the key as soon as you touch the door handles (or start button).
But again, maybe the European and US-verions of the keys are not the same.

 

I don't know how the keys work, but I do know that the car sending a signal to the key can't work unless the key is "listening" for it. That doesn't mean it's the same as being able to start the car, or open doors, but the key, at that time, is "on" to some degree.

 

No, the key is only "on", "listening" and reacting if there was movement of the key in the past minutes. Otherwise it will not react to the signal of the car.

 

Yeah, I guess that is the case most places. Noone would dare to touch my car here.

My car has the ventilated seats option (and most other options of course)

Just double click the lock button and wait for the red LED lighting up for approx a second, the key is now deactivated.

 

My key goes to sleep in the car after a few minutes. You can tell because it takes a couple of seconds for the car to wake the key up via the NFC pad before it starts. If you pick up the key and set it down, the car starts immediately because that wakes the key. This enhancement to the key's power cycle (sleep in car and be woken by NFC) might have come with the NFC and wireless charging. We always leave the key in the console in the garage.

 

The Owner's Manual for the 2019 E-Class Sedan (link below) clearly states FOUR times (pages 50-59) that, "When leaving the vehicle, always take
the key with you and lock the vehicle." I wonder why?

If you are replacing your key battery more often than once a year, then you have a true (objective) indication whether your key "goes to sleep"... or not when inside the vehicle.

Here's another experiment. Store the second fob well out of range, and it will go to sleep. When the key battery stored inside the car dies, you will have plenty of time to acquire a fresh battery while driving the car on the remotely stored fob for several months after.

https://www.mbusa.com/content/dam/mb...n_Operator.pdf

Think twice before suggesting that AMG Smart Keys are different from regular E-Class Smart Keys. They are not. The AMG owner's manual doesn't even have a reference to Smart Keys. None at all.

 

I read the manual. I don't know when the NFC pad was added but I think that's when the key behavior changed. I don't think it's an AMG thing. But I'm 100% certain my key sleeps in the car. I will continue to sleep well too.

 

You suggested another datapoint, which I just measured. I took delivery of the car, freshly made, in January. It came with two keys. One has been in a kitchen drawer, never used. The other has been used every day and stored in the console in a locked garage at night. I removed both batteries and measured their voltage:
Unused key: 3.0321 V
Used key: 3.0298 C

After 8 months, the key that is used every day and resides in the car has drained the battery to the extent of reducing its open-circuit voltage by 2.3 millivolts more than the key that has sat in a drawer, untouched. Typically, a CR2032 would not need replacement until its open-circuit voltage drops to 2.7 V. In other words, the key that spends its night in the car and the key that spends its night in the drawer are essentially identical with respect to their useful lives after 8 months.

 

I'm not worried about theft. That's not an issue around here. And it seems based on WHOOVER's results there isn't any difference between the key that's in my bedroom drawer and the key I leave in the car while parked in the garage. It's super convenient to be able to just get in the car and go so I'll keep doing that.