Alarm won't arm!
Thread Starter
Newbie
Joined: Aug 2025
Posts: 8
Likes: 1
From: Tasmania, Australia
CLS400 (218.365)
Alarm won't arm!
Hi, I noticed (after my partner's GLE got broken into) that the alarm on my 218 doesn't arm. I have checked with the dealer that it does indeed come with one, and they said it does. (They are totally unhelpful beyond this.)
However, I see no flashing light in the console to indicate that the alarm is arming, when I lock it. And it doesn't go off when I lock and then open it from inside, or even if I unlock it with the 'emergency key element' (with Keyless-GO deactivated). I'd like some help diagnosing this. Where do I start?
However, I see no flashing light in the console to indicate that the alarm is arming, when I lock it. And it doesn't go off when I lock and then open it from inside, or even if I unlock it with the 'emergency key element' (with Keyless-GO deactivated). I'd like some help diagnosing this. Where do I start?
Banned
Joined: May 2010
Posts: 1,209
Likes: 188
S65
Install trunk monkey.
Or, have the dealer tell you what codes they saw, if any. I suspect if it's supposed to work and it doesn't some module, somewhere left a code. Any phone app related settings? Do t use the app myself, so wouldn't know.
Or, have the dealer tell you what codes they saw, if any. I suspect if it's supposed to work and it doesn't some module, somewhere left a code. Any phone app related settings? Do t use the app myself, so wouldn't know.
MBWorld Fanatic!
Joined: Feb 2017
Posts: 2,303
Likes: 1,206
From: Baltimore County, MD
'13 s212 63 p30. '06 LX470
The alarm horns generally have a battery (replaceable through soldering) in them, but you really need to get a proper scan to know what the deal is.
MBWorld Fanatic!
Joined: Feb 2017
Posts: 2,303
Likes: 1,206
From: Baltimore County, MD
'13 s212 63 p30. '06 LX470
