R350 (W251) rear tail light issue-should I start with the SAM module??

Subscribe
May 17, 2025 | 02:00 PM
  #1  
Hello all, I am hoping I can get some advice on diagnosing and fixing rear tail light issues I am having on my 2006 R350. Currently, the auxiliary/secondary/back up bulbs are working. But the main tail lights and brake lights are not working. I have replaced the bulbs and that has not fixed the issue. I have read several places that it could be the SAM Module. I guess it is common for water to get into these modules and fry the connections. Should I start by inspecting the SAM Module? I purchased my R350 recently from the original owner who was an elderly man. This R350 is completely stock with no aftermarket wiring or stero equipment that could cause issues. There is no visible sign of water entering the rear area. But, that's not to say that at one point water could've gotten in. I am just wondering if anyone has experienced this issue and has some good advice that could save me some time. I am not very experienced with electrical issues on vehicles. I'm trying to see if I can repair this on my own instead of paying insane labor fees at a Mercedes shop. Any advice would be greatly appreciated! Thank you in advance!
Reply 0
May 17, 2025 | 11:05 PM
  #2  
Not a bad idea to inspect the rear SAM, it's at the top right of the spare tire compartment next to the fuse box. Would be hard for water to get onto it but not impossible. Are there any errors on the dash?

On the W251, the running lights are also the brake lights. The rear SAM dims them to half brightness for running light function.
Reply 0
May 19, 2025 | 11:43 AM
  #3  
@tsumi : thank you for your response to my post. I am seeing notifications on my dash such as "Rear left tailight, Rear right brake light, etc." notifying me that they are not working. But no other type of codes/error messages. The notifications are just like they would be if I simply had a burned out bulb. But like I said, I have replaced every bulb in the rear tail light and brake lights. The blinker lights and reverse lights seem to be unaffected? Any direction you can provide would be greatly appreciated!
Reply 0
May 19, 2025 | 01:38 PM
  #4  
Lights are controlled directly by the rear SAM. I would check to make sure all the contacts are clean and are making good contact in the bulb holders.
Reply 0
Subscribe
Currently Active Users (1)
 
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