Mercedes Sprinter Ends My Trip: “10 Starts Remaining” after OBD2 diagnostic code U010E “Lost Communication with Reductant Control Module”
Real science is never settled, and anyone who has certainty on such things is not qualified to discuss it.
UPDATE: turns out a rodent (rat or mouse) had chewed a wire under the driver seat box. I think this happened last August but somehow was a latent problem that showed up during my trip. I had repaired a chewed wire under the hood back in August 2021. So... one mouse or rat can disable your Sprinter very quickly if it gets the right wire!
Thank the US Environmental Protection Agency (EPA) and Mercedes Sprinter software engineers for this trip-ending problem, which is purely about emissions control, having nothing to do with vehicle performance or function.
TIP: purchase the extended warranty to its maximum duration for a Sprinter (7 years). Sprinters have too many problems to contemplate (godawful engineering for the engine + emissions systems + various other things). Negotiate a discount as I did. My extended warranty already paid for itself with replacement of the steering rack, and now this new problem.
Woe to anyone far from a dealer hoping to enjoy any kind of extended adventure, which is the raison d^etre of the Sprinter for any RV'er. And with the supply chain issues, you might have to wait a month or more for parts, effectively stranding you. Where I most often travel, it is 180 to 300 miles to the nearest Mercedes dealer, and ~300 miles home. Dog help you if you are in northern Idaho or Montana or Alaska!
Emissions failures are catastrophic because of software designed to fail
When/if the emissions systems on a Sprinter have even a minor problem, you are SOL. For example, the Sprinter will enter limp-home mode (25 mph) when DEF fluid runs out. Which it can if the DEF reservoir cracks and leaks its contents, as was a problem for many years with Sprinter and maybe still is. Otherwise, be sure to never let it drop below 50% full because crystals can develop inside in hot weather and fail it as well.
But it gets a lot worse: when communication to the AdBlue/DEF “reductant system” fails, the Sprinter enters a strictly limited period of inoperability, after which it becomes MUCH more expensive to fix because after ten starts it will lock (“brick”) various control modules. A huge repair bill ensues replacing all the intentionally failed/bricked control modules
The world-damaging problem this addresses? Slightly higher NOx emissions. Yeah, I 'get' that you can’t just let such things go on forever, but 100 starts would be a heck of a lot more reasonable than 10. And total vehicle failure instead of entering some “limp home” mode at 25mph and intentionally destroying (locking/bricking) control modules would be a lot more reasonable too.
Such is the state of modern emissions control hysteria. Fortunately, I have the extended warranty, and chose not to brick my Sprinter by going to 11 starts.
Mercedes has routinely engaged in hiding emissions problems, but vehicle reliability problems caused by poor design of key system components and crap-grade OEM oil are far more severe, though that is rarely if ever understood by Sprinter owners, who foot the bill or abandon the Sprinter outright (too expensive to fix), being deceived and lied-to about the root cause of the problems. But as to emissions, here is just one of the latest scandals. Systematic deception. More is coming here from US courts soon, which Mercedes is still trying to bamboozle. Earlier in 2021, Mercedes paid Sprinter owners of some model years $3500 cash in addition to repairs (the AEM recall).
Ten starts = you are fucked, no matter where, even if having a heart attack
Ten starts is half of what I might need for one day of activity, so it essentially means the trip is over. I could not stop and photograph or take a dump or whatever without letting the Sprinter idle continously. And idling is the kiss of death for a Sprinter, unlike a well-designd diesel engine, as shutting it off would use up a start. Nor could I go off on a hike with the keys in the ignition with the thing idling.
So I had no choice but to end my trip early and drive 300 miles straight home so I could take my Mercedes Sprinter adventure van into the Mercedes dealer first thing Monday morning.
Damian S writes:
As an independent European-car shop owner for over 15yrs I have seen my share of diesel emission problems with modern European vehicles. The reality is the emission standards are so tight on the diesels that the vehicle-owner pays the price and ends up stranded. Worse we are so handcuffed as an industry that independent shops largely avoid those repairs and send you off to see an official dealership. This is not unique to euros / modern domestic diesels have to meet the same standards. The upside to a domestic is your choices for servicing are better and the repair market has more knowledge
I own a 2006/2007 sprinter-based RV intentionally chosen because it is a pre-DEF vehicle and it is bullet-proof reliable as a Mercedes diesel should be. My advice to those that ask is to either go pre-DEF or avoid diesel. It's a sad comment on our modern motoring emission realities but soon enough we'll be all electric. Unfortunately there too the market is proving to have some real winners and real losers (go read up on the Chevrolet Bolt and then compare it to the BMW i3)... Sorry for your troubles you're caught in a big bad web that is impossible to 'win' in.
WIND: if you want the full scope on the problems with the Mercedes Sprinter, get all the info on it from Tom Stephens, below.
It’s not just independent shops that hate working on Sprinters. They have so many problems that dealers hate doing them too; there are far more profitable and headache-free non-Sprinter vehicles to work on. Fixing Sprinter problems related to the engine and emissions systems is whack-a-mole on steroids. Failure of one component almost always means all the others are badly degraded, even if not yet failed. Mercedes knows this and in essence the warranty and the Dieselgate litigation strategy is all about running out the clock on liability, and resisting to the last on fixing anything but the bare minimum. Which is less than the minimum needed.
Diesels have a well-deserved reputation for running with few issues for hundreds of thousands of miles. But that does NOT apply to modern diesels with complicated emissions technology, which is a science fair demonstration project. If properly designed, these modern diesels can be reasonably reliable, and I am sure that some brands do pretty well in that regard. But a modern Sprinter has major design weaknesses and all you can do is to mitigate those weaknesses, starting with an oil catch tank. An oil catch tank is beyond the technical grasp of most owners, and I’ve yet to find a shop that has any experience adding one, though I know of Sprinter owners who have installed themselves.