Heatwave

As I first approach my '07 R230 each morning in the garage and step to within 15' (or so) of the car, the SBC pump begins to cycle ... sounds like a compressor. The pump cycles off after 6 seconds (or so). By comparison, I have never heard the SBC pump in my wife's '07 W211.

How noisy is too noisy? Is this pumping sound an indication that the SBC is beginning to fail and needs replacement, or that it merely needs one of the "quietening kits" mentioned in other threads on this forum?

I note that MB extended the warranty on the SBC for a full ten years from date of first purchase. My ten-year mark will occur in April 2016. How badly does the SBC failure have to be to invoke replacement under warranty? What is MB's standard for determining when the SBC must be replaced?

What would you do if this were your car?

TTtodd

I am not going to be much help in the how loud department. However I can hear mine run for 5-6 seconds. I would say maybe once a week when I open the door. Never thought much of it.

cadbob

Ditto on noise department. I hear mine also. Glad I do!

Startech

Hope this helps

Heatwave

Star: Many thanks for that informative post. My car's SBC warranty is good through March 2016. The car is coming up on 37,000 miles ... will probably pass that mark today. So far, all is well.

carguyshu

they will only replace it if you get a message on the dash and then if a star tool determines that the reason the message came up is b/c replacement of the entire unit is necessary, such as when it reaches the end of its service life (this happens after 300,000 or so actuations). Replacement is about a $900 part. You can have anyone with a star tool tell you how many actuations it is at currently.

I know on the E's they had a service bulletin to add a hose that has a dampener on it to reduce noise. No such bulletin was released for the SL from what I can tell. My dad has an E55 and his is also much quieter than my SL even though he doesn't have the dampening hose.

I just had to order a new SBC as it reached the end of its service life. Parts guy said there have been over 12 different updated part numbers for the unit. Perhaps the noise has something to do with the exact part revision got put in each car.

carguyshu

Also, the pump should run after every 4 uses of the brakes. If you are sitting at a stop hit the pedal 3 times and then the 4th time push it hard all the way down. You should hear the pump run then. On the E it might be b/c of other noises like the airmatic pump running is why you might not hear it too.

brownboy

I have an '09 and was driving through the neighborhood when I got the bright red warning telling me that ABS and ESP were inactive and that more braking force would be required. The transmission wouldn't shift out of 2nd so I didn't drive fast and it took a lot of brake pedal force to stop even from 20mph. When I turned off the car at home I could hear (and feel) the SBC pump run for some time. After restarting a few times the warning light went away and the brakes worked fine. The cheapy scan tool didn't show any codes.

I was close to the dealership so I drove there. An hour later they said think it's an SBC pump issue but would need to diagnose more. They gave me a rental car and said they'd contact me in 4 days (I went in late on Xmas eve).

I see that there were recalls on this and that MB got rid of this system in all models several years ago except a few low volume ones like the R230. I also see that they were offering a 10 year / unlimited mile warranty on older cars that had this system. Anyone know if that applies to R231's? My extended factory warranty expired 6 months ago.

TIA

Television

In the UK we never got any extra guarantee for these pump, the 211 got a mod that included a damper to make it quieter.

Back to the 230. Many pumps got changed without the cars owner ever knowing, the main criteria is that it has to reach X pressure in X seconds.

The pump on my 2002 SL is the original, now a 89k miles, its always been very noisy, where as the pump on my 2009 SL is still very quiet at 50k miles.

There is nothing that one can do for noise. The pumps are wired into the car wake up, so you unlock or open a door and the pump will run. When code 2049 comes up its time out and new pump needed. Though Bosch are now doing exchange pumps the cost is till very high in the UK at about £1400 fitted, it is a 2 man job to bleed the system

brownboy

Update: after having my car for 2 weeks they replaced the SBC pump for free so that 10 yr / unlimited miles warranty must have saved me since my factory extended warranty of 7 years expired 6 months ago. I almost didn't take it to the dealership but I'm really glad I did now. They told me it would have cost $1500.

I set aside $10k when the warranty expired for repairs (not maintenance) and told myself I'd re-evaluate whether to keep this car when it runs out. We'll see how long the repair fund lasts but this is a good start. Any other hidden / separate warranties I should know about? Didn't know about this SBC thing until after I'd dropped the car off at the dealership and started researching.

I appreciate all of the great information in this thread and on this forum.