M-Class (W166) Produced 2012-2015

2015 W166 keyfob not working after 2days inside Faraday pouch

Thread Tools
 
Search this Thread
 
Rate Thread
 
Old Apr 22, 2025 | 04:39 PM
  #1  
nusoro's Avatar
Thread Starter
Newbie
 
Joined: Mar 2025
Posts: 11
Likes: 1
2015 W166 keyfob not working after 2days inside Faraday pouch

Left 2015 W166 key fob inside new Faraday pouch, after 2days the fob wunt unlock the vehicle.
At first, i though the fob battery was dead, so i replaced with a new battery. The infra-red light flashes on the fob but it still wunt unlock the doors
Bought the vehicle from auction site, it came with only one fob without a mechanical key and really stuck now.
Would appreciate your collective advice on this.
Thanks
Reply
Old Apr 22, 2025 | 05:57 PM
  #2  
W205C43PFL's Avatar
MBWorld God!
 
Joined: Dec 2019
Posts: 32,336
Likes: 6,315
Originally Posted by nusoro
Left 2015 W166 key fob inside new Faraday pouch, after 2days the fob wunt unlock the vehicle.
At first, i though the fob battery was dead, so i replaced with a new battery. The infra-red light flashes on the fob but it still wunt unlock the doors
Bought the vehicle from auction site, it came with only one fob without a mechanical key and really stuck now.
Would appreciate your collective advice on this.
Thanks
That is very strange, is there a second key to try.
Reply
Old Apr 22, 2025 | 08:13 PM
  #3  
streborx's Avatar
MBWorld Fanatic!
5 Year Member
Photogenic
Community Builder
Top Answer: 1
 
Joined: Oct 2019
Posts: 5,153
Likes: 1,767
From: Colorado
G550
It's unlikely the Faraday pouch had any damaging effect on the fob. More likely the previous owner damaged it, and it was a failure waiting to happen. There are many YT videos that offer troubleshooting and repair advice for MB keys which might be useful to view. Some auto stores have testers that can determine if your key is transmitting a signal. Contact a locksmith and see if your model's key can be replaced with an aftermarket key, or if it's a MB only key. In any case you need two key fobs with metal keys if you want to avoid future problems.
Reply
Old Apr 23, 2025 | 05:14 AM
  #4  
nusoro's Avatar
Thread Starter
Newbie
 
Joined: Mar 2025
Posts: 11
Likes: 1
Originally Posted by W205C43PFL
That is very strange, is there a second key to try.
There is no second key and no mechanical key on the fob
Reply
Old Apr 23, 2025 | 05:20 AM
  #5  
W205C43PFL's Avatar
MBWorld God!
 
Joined: Dec 2019
Posts: 32,336
Likes: 6,315
Originally Posted by nusoro
There is no second key and no mechanical key on the fob
You could try a new battery (specifically the panasonic one): https://mbworld.org/forums/c-class-w...ml#post8959680
Other than that, might have no choice but to tow it to a dealership and get a new key programmed, sorry OP : (
Reply
Old Apr 23, 2025 | 05:22 AM
  #6  
W205C43PFL's Avatar
MBWorld God!
 
Joined: Dec 2019
Posts: 32,336
Likes: 6,315
Originally Posted by W205C43PFL
That is very strange, is there a second key to try.
Sorry OP, not sure how I missed your post stating you only have one key.
Reply

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 


You have already rated this thread Rating: Thread Rating: 0 votes,  average.


All times are GMT -4. The time now is 03:43 AM.

story-0
6 Mercedes Models That Did NOT Age Well (But Are Somehow Still Cool)

Slideshow: Not every Mercedes design becomes timeless, some feel stuck in the era they came from.

By Verdad Gallardo | 2026-05-12 18:09:07


VIEW MORE
story-1
Manual Mercedes? 6 Times Sindelfingen Let Drivers Have All The Fun

Slideshow: Yes, Mercedes built manual cars, and some of them are far more interesting than you'd expect.

By Verdad Gallardo | 2026-05-02 12:36:58


VIEW MORE
story-2
Mercedes SLR McLaren 722 S Is Extremely Rare Example Modified by McLaren

Slideshow: A one-of-one U.S.-spec Mercedes-Benz SLR McLaren Roadster became even rarer after a factory-backed transformation at McLaren's headquarters.

By Verdad Gallardo | 2026-04-29 11:19:28


VIEW MORE
story-3
8 Classic Boxy Mercedes Designs That Have Aged Like Fine Wine

Slideshow: Before curves took over, Mercedes mastered the art of the straight line, and some of those shapes still look right today.

By Verdad Gallardo | 2026-04-25 12:05:49


VIEW MORE
story-4
Flawlessly Restored Mercedes 190E Evo II Heads to Auction

Slideshow: The 190E Evolution II shows how a homologation necessity became a six-figure collector icon.

By Verdad Gallardo | 2026-04-22 17:53:47


VIEW MORE
story-5
Electric Mercedes C-Class Unveiled: 11 Things You Need to Know

Slideshow: Mercedes is turning one of its core nameplates electric, and the details show just how serious this shift is.

By Verdad Gallardo | 2026-04-21 13:58:06


VIEW MORE
story-6
Mercedes EQS Gets A Major Update: Everything You Need to Know

Slideshow: Faster charging, longer range, and a controversial steer-by-wire system define the latest evolution of Mercedes-Benz EQS.

By Verdad Gallardo | 2026-04-15 10:35:34


VIEW MORE
story-7
5 Underrated Mercedes-Benz Models That Don't Get the Love They Deserve

Slideshow: These overlooked Mercedes-Benz models never got the spotlight, but they quietly delivered more than most remember.

By Verdad Gallardo | 2026-04-13 19:35:45


VIEW MORE
story-8
Mercedes 300D Has Pushed Well Past 1 Million Miles and It Ain't Stopping

Slideshow: A well-used 1991 Mercedes-Benz 300D with more than one million miles is now looking for a new owner, and it still appears ready for more.

By Verdad Gallardo | 2026-04-10 10:05:15


VIEW MORE
story-9
10 Most Reliable Mercedes-Benz Models You Can Buy Used

Slideshow: From bulletproof sedans to surprisingly tough SUVs, these Mercedes models proved that the three-pointed star can go the distance.

By Verdad Gallardo | 2026-04-08 09:55:49


VIEW MORE