Hi I have a 06 E350 with nearly 200k miles on it. Every now and then I would get this message "Reduced braking power start engine" and when I turn it on it would then say "Reduced braking power visit workshop." Upon restarting the car (sometimes it takes more than once) the message would go away and the car seems to drive fine. But when I drove with the message on it had the ABS error sign on and the brakes seemed a little off, and didnt feel like it was grabbing it. What might be the problem here?

 

Check Codes.
My guess is you have battery going bad, but that is what code will tell for sure.

 

I thought the second message was the SBC error message. Probably the pump. Probably no longer under warranty as that's 10 years from the in service date unless the car was a left over that sat on the lot.

 

how the heck is this a battery issue?

this is s warning that your SBC is gonna go anytime soon.
next thing ill see, you'll start a thread saying your car is a piece of junk coz you lost your brakes "without" any warning, then youll say youll never buy another Mercedes Benz and how you pay for so much money and it almost killed you.

 

Would you read the forum instead of typing your ego - you might learn something.
Those cars have brakes powered by electricity.
Low power = reduced brakes.

 

Says the guy who argues with everybody who doesnt agree with him. Lol

Me learn something? Definitely a lot, but definitely not from you either. All you do is stay up all day all night and posts replies on anything and anybody with your 60's advices. Then start an argument if anybody opposes you.

Bet you my 63 its the SBC goin bad.

 

Agreed, but load testing the SBC battery is a pretty cheap (free, most places) test to run.

 

+1 on this.

im well aware that SBC runs on aux bat. though more often than not, if this warning starts to show up, something really bad is about to happen.

 

My money is on C249F error - Operating time of Component of A7/3 is exceeded.

SBC Pump on it's last legs

 

This guy is hopeless.
But at least I have good chance to have 63 shipped to me from Australia

 

Im hopeless...
This coming from a guy who spells his name like this...

Krzysztof

What a dork! Hahaha

 

So I've ordered a new aux battery and will try to replace it once it arrives next week. Hopefully it indeed is just a battery problem and nothing more serious... I kinda don't want to spend 2k for a new SBC pump.

 

lets hope thatll fix your problem. but if i were you, ill start saving for the SBC, lets face it, your car is not getting any younger.

 

Yeah I wouldn't be surprised if it turned out to be the SBC though, especially with 200k miles on it... I'm just bummed that this had to happen after the 10 year warranty for the pump.

 

Instead of just guessing, take the car to an auto parts store like Advance Auto or Autozone and have them do a load test on the battery. They usually do it for free That will tell you if the battery is good or not and you won't waste money on something that might not be needed. How old is the battery?

 

The aux battery is about 5 years old, so I thought it's about time anyway.

 

Well it won't hurt. But you should get it scanned for codes to tell you what's really going on. A regular scanner won't do, you'll need to either take it to an MB dealer or get a scanner that can read MB specific codes. I don't think the SBC is 2k anymore, the price of the reman units keep coming down, but you're probably still looking at something over 1k.

 

After changing battery, check also grounding of SBC harness, many case where there has been poor contact and thus system detects low voltage and goes in warning mode.

 

Ok, I've installed the new battery and it seems it is ok.. for now. I usually get the warning message every other day or so, so we'll see if that fixed the problem or not in a couple days.

 

good on you mate. lets hope that fixes it. though id start saving up for the SBC, your car is long over due for it.

 

I forgot to update this thread so here's an update. Unfortunately replacing the auxiliary battery did not solve the problem and I had my mechanic put on a new sbc module. However after installing the pump he said he ran into some issues where the pump is not getting enough voltage (6 volts) for it to function. So he said it requires further diagnosis as to what the problem could be, so what could it be? Could it be the grounding of the sbc harness? Something as simple as fuse/relay? Or...?

 

where did you get the new sbc from? you sure its 100% functional before purchase?

 

It's a reman and I got it from a dealership. So I think the pump is good.

 

I have that messsage too, took it to a benz shop and they told me its the pressure accumulator upon hooiking up the star das, found it on ebay for 118.95 usd, also bought the brake light switch just in case.. Maybe its your brake light switch??

 

I doubt it's the brake switch. When it's the brake switch the message is in white not red and the braking is not affected. When I drive with the red message on I can definitely feel a decrease in braking power.