SL/R230: Sulfur burning smell coming from trunk/battery.
12-03-2018, 12:15 PM
#51
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No, FxFormat, but I did post the video of a very similar incident that occurred to a 2012 model in Hawaii back in 2013. . Same experience, although that Hawaii Owner caught it much earlier than I did.
By the way, I was told by my MB Service Advisor that even when someone is able to salvage their car, it is virtually imposible to get rid of that that toxic smoke smell if it got into the interior leather, the carpet and the headliner.
By the way, I was told by my MB Service Advisor that even when someone is able to salvage their car, it is virtually imposible to get rid of that that toxic smoke smell if it got into the interior leather, the carpet and the headliner.
Last edited by bob55; 12-03-2018 at 05:19 PM.
12-03-2018, 04:44 PM
#52
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2005 R 230 SL350 (M112 3.7). Sold the 1966 W113 230SL recently
That toxic smell is embedded into the carpet and headliners now, the smell will be there for awhile. It should be fine, i cut an access hole to my BCM so that i can check it, just put your hands on it every now and then before you drive, if it's stay cold then you're good, if it's hot/warm then something is shorting out again. Don't check it after a drive, check it before you drive. After a drive it'll get hot.
12-03-2018, 07:45 PM
#53
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Fxformat, can you post a picture of the access to the BCM? I did check my BCM and it looked pristine but it sounds like a good idea. One wonders if a temperature sensor like a clikson or clixon (as used in gas boilers) and some kind of warning could be a useful safety feature.
Oh i just cut a big square right into the trunk lining, that way when i want to i just lift it out of the way and inspect the BCM, the resale value is so bad on these cars that i don't think i'd sell it anyways. I love it, just have to deal with the headaches.
12-05-2018, 05:59 AM
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2015 ML350 (W166), 2010 E350 (sold), 2003 SL500 (sold)
SO TRUE!.....I WAS A VICTIM OF A 230 TRUNK FIRE WHICH OCCURRED INSIDE MY GARAGE AND WOULD HAVE BURNED MY HOUSE DOWN HAD I NOT CAUGHT IT WHEN I DID. IT TOTALED MY SL 500, BUT FORTUNATELY I WAS ABLE TO SAVE MY HOUSE AND MY OTHER (2) MB CARS WHICH WERE ALSO IN THAT GARAGE. MY WIFE AND I COULD HAVE EASILY BECOME VICTIMS OF CARBON MONOXIDE POISONING AS THE SMOKE AND FLAMES GOT INTO THE ATTIC AND SPREAD THROUGH THE
THIS WAS A VERY CLOSE CALL FOR ME AND MY WIFE AS WE WERE ABOUT TO TURN IN FOR THE NIGHT WHEN I WENT TO PUT SOMETHING I THE RECYCLE BIN, (WHICH WAS IN THE GARAGE). AS I OPENED THE DOOR LEADING TO THE GARAGE IT WAS FILLED WITH TOXIC BLACK SMOKE. I IMMEDIATELY POPPED THE GARAGE DOORS OPEN AND THEN SAW 5-FOOT HIGH FLAMES COMING FROM THE REAR PASSENGER SIDE OF MY SL 500 , HUST BELOW THE GAS FILLER CAP, THE REAR TIRE ON THAT SIDE WAS ALSO ON FIRE. BECAUSE OF THE LOCATION, OF THE FIRE., (VERY NEAR THE FUEL TANK), I WAS CONCERNED IT MIGHT EXPLODE AT ANY SECOND.
i WAS ABLE TOi DOUSE THE FLAMES WITH A GARDEN HOSE LOCATED JUST OUTSIDE THE GARAGE, BUT THE CAR WAS STILL BURNING INSIDE THE TRUNK WHICH WOULD NOT OPEN AS NORMAL.. hOWEVER, WHEN THE FIRE DEPARTMENT ARRIVED, i WAS ABLE TO OPEN THE TRUNK USING THE 'MANUAL FLAT KEY' WHICH I REMOVED FROM THE MB SMART KEY. THE FIRE DEPARTMENT PUT OUT THE SMOLDERING FIRE INSIDE THE TRUNK, BUT THE BATTERY MODULE KEPT SPARKING UNTIL BOTH BATTERIES WERE DISCONNECTED..
MY EXPERIENCE WAS A NEAR DISASTER FOR SURE!
IF YOU ARE THE OWNER OF AN SL 230 SERIES YOU NEED TO BE AWARE THAT THE BATTERY CONTROL MODULE IN THESE CARS IS A VERY FIRE HAZARD THAT CAN IGNITE WITHOUT WARNING. iN FACT, iN MY CASE, THE CAR HAD NOT EVEN BEEN DRIVEN FOR 3-DAYS WHEN THE TRUNK/GARAGE FIRE OCCURRED. .
THERE HAVE BEEN QUITE A FEW OF THESE 230 TRUNK FIRES, (2003-2012 SL MODELS) ,SO i AM QUITE SURPRISED THERE IS STILL NO CLASS ACTION LAWSUIT OVER THIS PROBLEM HOWEVER, IT HAS STILL NOT OCCURRED!
IT OCCURRED TO ME THAT MY WIFE AND I COULD HAVE EASILY DIED FROM CARBON MONOXIDE POISONING IN OUR SLEEP BECAUSE THE TOXIC WAS ALREADY ENTERING THE ATTIC AND ONCE THERE IT COULD HAVE EASILY TRAVELED TO OUR BEDROOM VIA THE A/C VENTS. WE MIGHT NEVER HAVE HEARD ANY OF THE (8) SMOKE ALARMS ILOCATED INSIDE OUR HOUSE.
THIS WAS A VERY CLOSE CALL FOR ME AND MY WIFE AS WE WERE ABOUT TO TURN IN FOR THE NIGHT WHEN I WENT TO PUT SOMETHING I THE RECYCLE BIN, (WHICH WAS IN THE GARAGE). AS I OPENED THE DOOR LEADING TO THE GARAGE IT WAS FILLED WITH TOXIC BLACK SMOKE. I IMMEDIATELY POPPED THE GARAGE DOORS OPEN AND THEN SAW 5-FOOT HIGH FLAMES COMING FROM THE REAR PASSENGER SIDE OF MY SL 500 , HUST BELOW THE GAS FILLER CAP, THE REAR TIRE ON THAT SIDE WAS ALSO ON FIRE. BECAUSE OF THE LOCATION, OF THE FIRE., (VERY NEAR THE FUEL TANK), I WAS CONCERNED IT MIGHT EXPLODE AT ANY SECOND.
i WAS ABLE TOi DOUSE THE FLAMES WITH A GARDEN HOSE LOCATED JUST OUTSIDE THE GARAGE, BUT THE CAR WAS STILL BURNING INSIDE THE TRUNK WHICH WOULD NOT OPEN AS NORMAL.. hOWEVER, WHEN THE FIRE DEPARTMENT ARRIVED, i WAS ABLE TO OPEN THE TRUNK USING THE 'MANUAL FLAT KEY' WHICH I REMOVED FROM THE MB SMART KEY. THE FIRE DEPARTMENT PUT OUT THE SMOLDERING FIRE INSIDE THE TRUNK, BUT THE BATTERY MODULE KEPT SPARKING UNTIL BOTH BATTERIES WERE DISCONNECTED..
MY EXPERIENCE WAS A NEAR DISASTER FOR SURE!
IF YOU ARE THE OWNER OF AN SL 230 SERIES YOU NEED TO BE AWARE THAT THE BATTERY CONTROL MODULE IN THESE CARS IS A VERY FIRE HAZARD THAT CAN IGNITE WITHOUT WARNING. iN FACT, iN MY CASE, THE CAR HAD NOT EVEN BEEN DRIVEN FOR 3-DAYS WHEN THE TRUNK/GARAGE FIRE OCCURRED. .
THERE HAVE BEEN QUITE A FEW OF THESE 230 TRUNK FIRES, (2003-2012 SL MODELS) ,SO i AM QUITE SURPRISED THERE IS STILL NO CLASS ACTION LAWSUIT OVER THIS PROBLEM HOWEVER, IT HAS STILL NOT OCCURRED!
IT OCCURRED TO ME THAT MY WIFE AND I COULD HAVE EASILY DIED FROM CARBON MONOXIDE POISONING IN OUR SLEEP BECAUSE THE TOXIC WAS ALREADY ENTERING THE ATTIC AND ONCE THERE IT COULD HAVE EASILY TRAVELED TO OUR BEDROOM VIA THE A/C VENTS. WE MIGHT NEVER HAVE HEARD ANY OF THE (8) SMOKE ALARMS ILOCATED INSIDE OUR HOUSE.
I am new to MB World and this is my first post to this thread and I, like many of you, finally bought the "car of my dreams" two years ago (2003 SL500, one owner, Florida car, 36k miles, $17,000). In spite of all my extensive research I was not prepared for the litany of potential problems this "engineering masterpiece" could potentially cause. Over the past two years I've had my share of problems (most of them minor which I was able to repair myself thanks to MB World) but I must admit this one "scares the hell out of me". It's tough going to bed at night with this "TIME BOMB" ticking in the garage!
My wife and I make multiple trips to CT (5-6 times a year, 2-6 weeks duration) and I leave the SL home in the garage. Am I to understand I should be disconnecting the batteries each time we go away? Of course my fear is we will return home one day to find the house has burned down!!
I'm unclear whether to believe this condition is the result of a defect, faulty design, old age, spontaneous combustion, water leak, non OEM batteries, or just the luck of the draw. I'm also unclear whether one should just wait until there are symptoms present before addressing the problem
or bite the bullet and do something about it now. A brand new OEM BCM can be purchased for less than $700....a small price to pay for saving your home!!
Furthermore, I fail to see the logic in purchasing a used BCM on E-bay as a replacement when that part is probably just as defective as the one you removed. Does anyone know if the new unit available today has been redesigned to eliminate this potential fire hazard?? It's evident to me
that replacing the unit is a simple procedure and I'm having a hard time weighing these options against the very hard decision of just getting rid of the car. However (like most of you) I love the car, it's a joy to drive and it's the best car I've ever owned....
Finally, it's obvious I'm looking for guidance and advice from people that are more knowledgeable and experienced than I regarding this matter and all comments and advice would be greatly appreciated.
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StirlingMoss722 (01-26-2020)
12-05-2018, 01:06 PM
#55
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That toxic smell is embedded into the carpet and headliners now, the smell will be there for awhile. It should be fine, i cut an access hole to my BCM so that i can check it, just put your hands on it every now and then before you drive, if it's stay cold then you're good, if it's hot/warm then something is shorting out again. Don't check it after a drive, check it before you drive. After a drive it'll get hot.
12-05-2018, 01:21 PM
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Furthermore, I fail to see the logic in purchasing a used BCM on E-bay as a replacement when that part is probably just as defective as the one you removed. Does anyone know if the new unit available today has been redesigned to eliminate this potential fire hazard?? It's evident to me that replacing the unit is a simple procedure and I'm having a hard time weighing these options against the very hard decision of just getting rid of the car. However (like most of you) I love the car, it's a joy to drive and it's the best car I've ever owned....
I do like the idea of cutting an access hole in the carpet. Taking the trunk trim apart is a PITA, even in service mode.
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StirlingMoss722 (01-26-2020)
12-05-2018, 01:25 PM
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12-05-2018, 03:59 PM
#59
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Haha how about if Merc an Bosch would be willing to confirm in writing that this distinct smell is not caused by carcinogenic substances, evaporating at a persistently stable pace?
But really, we’re all somewhat concerned and not without reason. I would be willing to locate a suitable officer at MB HQ and/or Bosch and urge him (bet it’s a man) to have a suitable substitute developed, 100% plug & play, for a VERY reasonable price. If a giveaway is too much honesty for them. After all they did agree to cover their tricky brake-by-wire system for a quarter of a century (in the US only??).
(I was in Japanese semi-gov service, developing J-NL business and after that I’ve been setting up business arrangements between NL, Europe and the US).
The way to go is
1- most flies (not all) you catch with honey, not vinegar.
2- the head entrance, secretaries, public statements, those will probably all cause a defensive strategy. It’s a person we would need to get to.
3- Germany being Germany, one had better gone the German way (ethics, understanding decision making, honouring a great great automotive heritage. WE have a problem together, you the maker us the owners at risk. Stuttgart reading this? (who knows) - fine, step 1 in a reasonable professional journey.
4-I own a W113 (selling) so there’s contacts in the classic environment. Could be useful.
How about it. If this catches on in US, Europe, elsewhere, we can set up something, perhaps on neutral ground (inventory, ordering, delivery, DIY/dealer option).
But really, we’re all somewhat concerned and not without reason. I would be willing to locate a suitable officer at MB HQ and/or Bosch and urge him (bet it’s a man) to have a suitable substitute developed, 100% plug & play, for a VERY reasonable price. If a giveaway is too much honesty for them. After all they did agree to cover their tricky brake-by-wire system for a quarter of a century (in the US only??).
(I was in Japanese semi-gov service, developing J-NL business and after that I’ve been setting up business arrangements between NL, Europe and the US).
The way to go is
1- most flies (not all) you catch with honey, not vinegar.
2- the head entrance, secretaries, public statements, those will probably all cause a defensive strategy. It’s a person we would need to get to.
3- Germany being Germany, one had better gone the German way (ethics, understanding decision making, honouring a great great automotive heritage. WE have a problem together, you the maker us the owners at risk. Stuttgart reading this? (who knows) - fine, step 1 in a reasonable professional journey.
4-I own a W113 (selling) so there’s contacts in the classic environment. Could be useful.
How about it. If this catches on in US, Europe, elsewhere, we can set up something, perhaps on neutral ground (inventory, ordering, delivery, DIY/dealer option).
12-05-2018, 04:20 PM
#60
Senior Member
Just a question here; have those that have experienced this issue reported it to the NTHS? Did they or their insurance companies that encourage a loss seek recourse from MB? If so, what were the responses? What percentage of the total production has had this issue?
It would be good to know these things prior to trying to get resolution from MB.
It would be good to know these things prior to trying to get resolution from MB.
12-06-2018, 10:38 AM
#61
Junior Member
I am horrified to find out yet another flaw in this beautiful car. I have been through the replacement of the ABC system (2 new pumps, and 4 new struts), I have fixed the faulty loose headliner (gorilla glue), and I have fixed the faulty flap thing on the deck lid. I feel lucky to get through just one month without seeing some damn fault code come up on the dash and live in fear every time I put up or put down the top because I know that faulty design issue will be next. This battery starting on fire with the car just sitting there issue is too much. I am putting this thing up for sale and getting rid of the worry. I think I will start looking for a Viper to replace it. Thank God for this forum!
12-06-2018, 01:15 PM
#62
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As someone said earlier, the BCM in the 230 Series is 'a ticking time bomb' that can start 'sparking' and catch fire at any time. The hazard remains as long as the (2) batteries are connected.
When my trunk fire incident happened, the car had been sitting in my garage, (un-driven), for 3 full days!.
It is essential that all 230 owners be made aware of this risk! There really should have been a Class Action Lawsuit over this!
When my trunk fire incident happened, the car had been sitting in my garage, (un-driven), for 3 full days!.
It is essential that all 230 owners be made aware of this risk! There really should have been a Class Action Lawsuit over this!
Last edited by bob55; 12-07-2018 at 12:21 PM.
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StirlingMoss722 (01-26-2020)
12-06-2018, 01:30 PM
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That was precisely my point, Bob. When my wife and I make our routine trips up north (we're actually leaving tomorrow for three weeks) am I expected to disconnect my batteries while we're gone ???
12-06-2018, 02:10 PM
#64
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I believe this is caused by failing electrolytic capacitors. Back in the early 2000's, there was a rash of capacitor failures due to defective parts being made in Taiwanese factories. I doubt those capacitors made their way into these BCMs, but capacitors can still fail. Usually it's because of excessive heat, which can be caused by the environment, but also if the wrong capacitor size it used for the application. One thing I noticed about the ones in Frederick's photo above is that they don't have "stress-crimps" on the top. Most e-caps have that so if they fail, the pressure pops open the top and the internal gases are vented. In this case, maybe the gases are causing the bottom of the e-cap to blow out, then short out, and then cause the fires. Of course then why are they failing? I would assume that the maker of the circuit board used properly sized capacitors, and that they aren't getting beyond their operating temperature in the trunk. but pulling too much current due to, say, a weak battery, or water intrusion causing a short could be the cause. These are just some armchair theories, of course. In the mean time, I recommend inspecting the unit and regularly smelling your trunk for any possible signs of electrical burning.
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StirlingMoss722 (01-26-2020)
12-06-2018, 02:51 PM
#65
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I saw German eBay offers for complete trunk liners, against very reasonable prices. Would be like dragging elephants across the ocean, parcel wise. But if you can lay your hands on a set in the US, it would ondoubtedly be more effective than cleaning your smoked liner rigorously.
Meanwhile, I don’t think my proposal about approaching MB/Bosch is getting much attention or support. Other ideas welcome!
I don’t feel too happy about what’s going on in my trunk. If anything, doing nothing is the bad option.
Meanwhile, I don’t think my proposal about approaching MB/Bosch is getting much attention or support. Other ideas welcome!
I don’t feel too happy about what’s going on in my trunk. If anything, doing nothing is the bad option.
12-06-2018, 05:05 PM
#66
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Yeah i would if i were you, disconnect both batteries, i had mine disconnected for 2 weeks while waiting for the BCM and time to put it back in, fired right up and didn't lose any settings or had to do anything special. 2005 SL600
12-06-2018, 05:14 PM
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Regarding RUDENEY quote:<br /><br />That is the most thought provoking, common sense, knowledgeable explanation I've read thus far on this thread regarding this issue. I am beginning to formulate an additional armchair theory that perhaps included in the "root" of all these fire/disasters is not replacing the batteries with OEM Mercedes batteries. I'd be curious to know how many after market batteries in coordination with BCM were involved in these fires.???
Last edited by DomiNOOCH; 12-06-2018 at 05:44 PM.
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StirlingMoss722 (01-26-2020)
12-06-2018, 09:42 PM
#68
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I doubt it has anything to do with aftermarket batteries. The chemistry of a lead acid battery is fairly simple. They put out 12.6v and charge best with about 14v. Now, a failing battery where the plates warp and short out internally can act like a giant resistor. This could cause the BCM to try to put out more power, which the battery then converts to heat. Of course this can happen to any lead acid batter y- MBZ brand, Varta, Interstate, etc.
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12-07-2018, 10:45 AM
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Does it seem these failures seem to happen after the car has sat for a few days without a tender? My SL is a daily driver and does get driven almost daily since I bought it. Mine failed after I went away for a long weekend and the car was sitting without being on a tender.
Just curious if the combination of age of the car and not having a charge applied can cause an issue over an extended period.
Just curious if the combination of age of the car and not having a charge applied can cause an issue over an extended period.
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StirlingMoss722 (01-26-2020)
12-07-2018, 02:00 PM
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Does it seem these failures seem to happen after the car has sat for a few days without a tender? My SL is a daily driver and does get driven almost daily since I bought it. Mine failed after I went away for a long weekend and the car was sitting without being on a tender.
Just curious if the combination of age of the car and not having a charge applied can cause an issue over an extended period.
Just curious if the combination of age of the car and not having a charge applied can cause an issue over an extended period.
My rear battery has been getting weaker(battery offline message after 1 week every startup)..I hooked it up to a solar charger for precautions.
But def paranoid now, I heard about this before but after reading BOB's story that's insane.
How is a mass NHSTA thing not active..sorry to hear 57
Keeping mine outdoors now..
If it's been happening to new cars 5-10 years ago that might eliminate the age issue, otherwise huge defect if every car was affected by it..
Last edited by Das Geld 2; 12-07-2018 at 02:03 PM.
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StirlingMoss722 (01-26-2020)
12-10-2018, 03:16 PM
#73
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There is more info on the BCM Fire Hazard in the linked thread shown below....Just click on it to see other incidents of trunk fires related to the Battery Control Module in the 230 Series.
https://mbworld.org/forums/sl-class-...unk-fire.html?
https://mbworld.org/forums/sl-class-...unk-fire.html?
02-01-2019, 12:46 AM
#74
Thank you @FxFormat for starting this thread and replying to my PM. My resolution, I had to replace a blown fuse (100 amp) passenger side under the floorboard and the BCM old part # 2305400945 was replaced with a newer version 2305401045 from a 04 SL500 the local dismantler wanted $300. My Visit Workshop went away after I cleared the codes with my MBll.
07-19-2020, 04:53 PM
#75
Junior Member
There have been many SL230 Trunk Fires! This is a serious fire hazard that MB is yet to address!
This fire hazard is an issue for ALL 230 SL Class Vehicles from 2003-2012 and may also be an issue with the new 2013 through current year 231 Series of SL Class vehicles.
It's likely not the battery like you think...Click on the thread below and be sure go to YouTube to view the video referenced there so you can see the exact location of the culprit (an electronics module) that tends to short out and is causing all these SL trunk fires. Again, this is a very serious fire hazard...Get your 230 SL to a MB Dealer so it can be checked out ASAP!
https://mbworld.org/forums/sl-class-...runk-fire.html
This fire hazard is an issue for ALL 230 SL Class Vehicles from 2003-2012 and may also be an issue with the new 2013 through current year 231 Series of SL Class vehicles.
It's likely not the battery like you think...Click on the thread below and be sure go to YouTube to view the video referenced there so you can see the exact location of the culprit (an electronics module) that tends to short out and is causing all these SL trunk fires. Again, this is a very serious fire hazard...Get your 230 SL to a MB Dealer so it can be checked out ASAP!
https://mbworld.org/forums/sl-class-...runk-fire.html
My question is: Does having (and using) a battery cutoff switch on the rear-mounted consumer battery (AKA systems battery) reduce the chances of a failing battery control module (BCM) causing a serious electrical fire as the BCM components age? The BCM receives 12 volt input power from both the front and rear-mounted batteries, but it is not clear to me if using a rear-mounted battery cutoff switch would improve the situation at all. My SL600 initially had a pretty serious parked battery drain problem on the consumer battery, but that situation seems to have corrected itself with more frequent use of the car and my long-term battery drain now measures 25-30 milliamps (normal for a modern car with various computer circuits shutting down) after removing the key. When I measured the parked current drain a number of weeks ago, it was too high, at around 120 milliamps; that change, while a good thing, also scares me a little bit, because it might point to a failing BCM. I can think of no other reason for the change in current measurements on this car.
