hitch02

All -

Everything has been going great since I bought the car about 2 months ago. Mileage is about 61K.

This morning on my regular commute, I was sitting at a stoplight, and when I went to accelerate the car just stayed put, and all the dash lights came on. It basically didn't re-start after it did the auto stop bit. Put it in park, pushed the ignition button, fired right up normally. No CE or other warning light.

Thinking it may have been a fluke, I went on. As I pulled into the alley where my parking garage is located, maybe 5 minutes later, same exact thing.

So I am thinking it has to do with the start-stop system, but I am concerned that if I take it in, since there are no CE or warning lights/messages, the shop won't really be able to do much if anything with it.

Is there a way to disable start-stop? At least as an interim possible fix? Other thoughts on potential cause/fix?

Thanks!!

-Reed
'10 S400 Hybrid
'11 E350 4Matic Wagon
'85 300SD

Mike5215

So YOU'RE the guy who bought the S400 hybrid. We were wondering when you were gonna show up. But seriously, the forum collectively knows almost nothing mechanically about our own gas powered cars. We mostly talk about sex and occasionally help each other pick out new wheels.

But I'm guessing even without a dash warning the car stored a fault code each time and your dealer or indie can pull it for you.

See? Even when we try to behave ourselves a sex joke comes out.

hitch02

Nice!

Yes, I am one of the few, the proud, the guys who live in Northern VA and can use the carpool lanes to get to work in an "approved" hybrid, assuming you have a set of the old, grandfathered license plates.... My preference would've been the S600.... These cars really are sort of idiot-******* unicorns, but when they work they are pretty nice to drive.... Not V8 nice, but close..

I spoke with my indie after posting this and he told me that although he test drove one in 2010, he has yet to actually work on one. That said, he does have the latest equipment and software and thinks he can help, but said he would eat the diagnostic time if he can't. The best I can tell, there's a good chance that the 12v battery is old and dying. If not that, then I am scared for my financial future and the possibility of my kids going to college...

Should be fun. Thanks for the reply!!

-Reed

MBNUT1

keep us posted on your progress on this.

alx

Check 12v battery and charging. If ok, send car back to the alien planet you got it from.

hitch02

So the independent shop checked it out, and when they determined it was not a straight-up mechanical problem told me to send it to the dealer. As promised, they didn't try and charge me for the diagnostic time, but said that one of the MB-Certified Hybrid techs should check it out. I am holding out hope that it is the 12v system, but still the cost potential here is astounding and I an trying to brace for impact......

Car is being looked at by the Hybrid tech tomorrow. Stay tuned....

-Reed
'10 S400 Hybrid
'11 E350 4Matic Wagon
'85 300SD

hitch02

So, to close the loop on my situation....

The problem was unfortunately not the 12v system, although that's what the dealer looked at first. What they found was a failing Power Electronics Module - Start/Stop (P/N 000 906 4703). Apparently this was the second one of these with the same problem that this dealer had seen in as many months. In any case, initial quote from the dealer to repair was $900 labor and $11,400 for the part. Three minutes on the internet, several days, and some intervention from MBUSA left me with a part cost of $6400, and after labor and tax repair cost of $7,700. Looking at other hybrid-specific parts (including a hybrid battery that has been upgraded and now costs double what it used to) I decided to trade it on a 2013 E350 BlueTEC. Even the MBUSA folks told me it was a catastrophically expensive car to own outside of warranty. Shame, because I really liked it when it worked, but that said I prefer the driving characteristics of the V6 diesel by a longshot, not to mention significantly better mileage.

Contemplating an S400? Don't. Buy the S550 or the S350 BlueTEC if you have to have the W221 (and I TOTALLY get why you'd want one...). Thanks for the feedback along the way.

-Reed
ex- 2010 S400 Hybrid (60,500 miles)
2013 E350 BlueTEC 22K
2011 E350 4Matic Wagon 48K
1985 300SD Turbodiesel 114K

bzliteyear

wow...sad story - probably also explains why the hybrid resale values are so poor on the Porsche hybrids as well, though seems ok on the Lexus/Toyota hybrids.
PL

MBNUT1

Thank you for saving me from a S400 hybrid and contributing to my being able to retire on time.

Prochambers

$11,400 down to $6400 for the part? That's insane! I wouldn't trust a hybrid at all.

DaveW68

Since BMW and Prius drivers have the well earned reputation of being the biggest a$$hole drivers on the road, you could easily surmise that the Prius has earned that distinction due to their owner's uppity attitude about driving a hyhrid. I'm sure we'll see more and more hybrids make it onto that list as more of them come out and become more popular.

My point of this is that society will look upon you as being a nicer person if you just buy a regular gas or oil burner S class.

KNBS550

Thanks for refreshing this thread. I was actually starting to look at reasonably priced S400 hybrids ($40K). Reading about Hitch02's problems put the kabosh on it. I also noticed that very few hybrids are CPO'd by Mercedes dealers. I wonder why???

MBNUT1

That is exactly where I was until I read this. 2010 W221 for 25K, count me in. Oops....

S550v

I read elsewhere that to replace the Li-Ion battery with labor is above $20k, the battery itself is 1/2 the cost. That put the brakes for me when I was looking for a S400 a few years back.

sanjay28

I wish I had read this thread (or found this forum) before I purchased my S400. I have the same problem...$36,000 to repair. I understand that this specific model is an exception to otherwise high quality cars, but I'm a little "gun-shy" from getting about getting another Merc. Am I over thinking it?

KNBS550

So are you experiencing the same shutdown? They quoted you $36K, did they say what it would cover?

konigstiger

If diagnosed as power electronics have dealer check VMI to see if your VIN is included in service campaigns 2012080004 or 2015030006 (see attachments) if so, repair is free. FYI For bulletins & service campaigns search “hybrid” here: https://mbworld.org/forums/s-class-w...tins-date.html

sanjay28

This was the recommended repair... "Electric Motor Control Unit & High Voltage Battery must be replaced per LI 54.10-P-054690". I had several conversations with the dealer and corporate and they offered to fix it for $20k. I appreciate their offer, but $20k to fix a car worth $15k is just not worth it.

konigstiger

Bulletin and SCs seem to be same subject matter.

sanjay28

My car has almost 100k miles on it but since I had all of the maintenance done, I know it is still good for another 100k (aside from the battery issue). I'm just going to trade it in for another car, but I really want another S and the only one the dealer will give me a good deal on has 99k miles. Is that too many miles for a Merc (this is/was my first one)?

anniqu

Hello

Where did you find the module for $ 6400.00

konigstiger

MB supplied part at a discount: “intervention from MBUSA left me with a part cost of $6400”.

tusabes

Anyone still driving these ?

E420

2010s400

I have one just bought it last night. Kind of scared to drive it after this forum tho. Any issues you have? Mine gave me a scare today as it wouldn't start on my driveway. Went to store with my other car and came back and tried again and it started.