Notices
Mercedes Tech Talk Discuss general technical questions and issues about your Mercedes-Benz. Moderated by a certified MB Tech.
Sponsored by:
Sponsored by:

SL55 - check engine - lots of unrelated errors

Thread Tools
 
Search this Thread
 
Rate Thread
 
Old Jun 9, 2011 | 02:47 PM
  #1  
Richard's Avatar
Thread Starter
MBWorld Fanatic!
 
Joined: Nov 2001
Posts: 1,148
Likes: 16
From: Berkshire, UK
2004 SL55, 2015 A250d, 2016 GLC250d
SL55 - check engine - lots of unrelated errors

Hi All,

My SL55 check engine light came on, so I put it on Star Diagnosis and it shows the following.

P20BE-004 G3/4 (Right O2 sensor, before TWC[KAT]: Open circuit in sensor heating line (P0135)
P20BF-004 G3/3 (Left O2 sensor, before TWC[KAT]: Open circuit in sensor heating line (P0155)
P20C2-004 G3/6 (Right O2 sensor, after TWC[KAT]: Open circuit in sensor heating line (P0141)
P20C3-004 G3/5 (Left O2 sensor, after TWC[KAT]: Open circuit in sensor heating line (P0161)
P2026-002 Y58/1 (Purge control valve): Short circuit to ground / Switchover valve permanently open (P0445)

I find it strange that I have 5 different faults (and 4 similar), so either only 1 of them caused the Check Engine lamp, and the other 4 have been there a while or something more sinister (like engine management system) is failing.

The wiring for the before and after O2 sensors doesn't go to the same connectors as each other, only the power supply is common, but not same power supply for Y58/1 Purge control valve

Car is 7 years old, done 25K miles

Any ideas anyone ??

Thank you !

Richard
Reply
Old Jun 9, 2011 | 06:59 PM
  #2  
Ausmbtech's Avatar
MBWorld Fanatic!
 
Joined: Jan 2007
Posts: 1,152
Likes: 29
From: Sydney, Australia
190D 2.5 (x2), 190E 2.6, W202 C240,W202 C43 (C55), W210 E55, W212 E250CDI
With the 4 o2 sensor codes I'd say the exhaust has been removed and the ignition switched on at some point in it's life. I'd clear all the codes and drive it for 2 weeks and see what comes back. I think they are older faults, the purge valve is likely to be the code that will come back.
Reply
Old Jun 10, 2011 | 03:25 AM
  #3  
Richard's Avatar
Thread Starter
MBWorld Fanatic!
 
Joined: Nov 2001
Posts: 1,148
Likes: 16
From: Berkshire, UK
2004 SL55, 2015 A250d, 2016 GLC250d
Thanks I did clear the codes and all came back straight away car was driven

Do the purge valves fail often?

Richard
Reply
Old Jun 14, 2011 | 09:46 AM
  #4  
Richard's Avatar
Thread Starter
MBWorld Fanatic!
 
Joined: Nov 2001
Posts: 1,148
Likes: 16
From: Berkshire, UK
2004 SL55, 2015 A250d, 2016 GLC250d
And the answer was ..

The Purge control valve (Also known as Regeneration valve) had failed and blown the fuse in the passenger side fusebox that powers the regeneration valve, the O2 sensors and a charcoal filter valve (can't remember what the additional fault code that came up was for that).

New fuse got rid of all the errors except the Purge Control Valve, new Purge Control Valve sorted that

And now the O2 sensors are working, I realise that it had been not performing as smoothly / well.

Cheers

Richard
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 11:57 PM.

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