Originally Posted by PancakeBimmer

Sorry for bump, but hoping that OP or maybe someone else who has done this procedure with DAS software can chime in. I am flushing and bleeding brake system after SBC replacement. SBC is passive.

Does SBC have to be active or passive for first step where bleeder system is connected and pressurized to 2 bar? It instructs to raise brake bleeder pressure to 2 bar and open bleeder screw. At this point only brake bleeder's pressure is pushing fluid, right? In my case fluid came out with pressure from brake bleeder only.

Then DAS instructs to switch off filling and bleeding equipment. Does that mean that bleeder screw has to be closed? I closed the bleeder screw at this step and pressed F3 and it showed the step to connect filling and bleeding system with pressure 0.5 bar. It doesnt say if bleeder should be open or closed, but I did close it at previous step. After pressing F3 again SBC pump starts building pressure. This is where rear right hose blew. This happened before DAS instructed to reduce pressure at filling and bleeding to 0bar and switch it off. Then wait and switch it back on.

After replacing broken hose I ran the procedure again the same way, but this time at the same step rear left brake hose blew (while bleeding rear right).

At this point I am pretty sure that I messed up by closing bleeder screw and should have had it open until DAS instructed to close it.

How far off am I?

Originally Posted by isthisit

Hi, I tried to do the bleeding procedure but in the middle of it the battery voltage showed too low and star asked for a charger to be connected... Do I connect the charger to the main battery in the trunk or to the small SBC battery under the hood? thank you so much in advance.
-G

Originally Posted by Cliviscus

Excellent instructions and thanks.
Is the sequence of bleeding relevant to right hand drive cars?

Originally Posted by bbirdwell

The use of star /Xentry diagnostic to bleed the SBC system is not so much to remove the air as it is to remove all of the old fluid. The SBC system is a recirculating system not a dead end system like standard hydraulic brakes. Yes SBC calipers are dead ends in the system but there are multiple crossovers between the various hydraulic lines. The STAR system opens and closes valves in a defined sequence so as to remove all of the old fluid as well as any air trapped in the cross connections.
If I remember correctly, the star bleed sequence is right rear, left rear, left front, right front. On the front calipers you bleed the inboard Pistons then bleed the outboard Pistons.
Perform an advanced search and you should find the technical documentation on the SBC system.

Originally Posted by Obaid1999

thanks much for the reply, but every time I seek help I get more confused. Ok what do you mean by saying On the front calipers bleed the inboard Pistons then bleed the outboard Pistons.? from what I understood is that you may think that there is 2 Bleeder screws on each front calipers which is not

Originally Posted by UncleBenz55

When doing the procedure, Star tells you in which order to open what valve. I'd recommend it, as it also does an sbc test.

Originally Posted by BrianS

I decided it was about time to flush the system and figured another DIY might be helpful. The entire procedure took about 2.5 liters of fluid.

Here's the main supplies I used...STAR, Motive bleeder, and Pentosin Super Dot 4 which is the MB spec and OE part from what I can find, http://www.crpindustries.com/pentosi...uperDOT4_3.pdf , but much less at NAPA ($13 per liter) than going to the dealer for the same thing in an MB bottle. You'll also need an 8mm wrench for the rear bleeders and a 10mm for the front caliper bleeders.



First I sucked out as much of the old brake as I could from the reservoir using a 60cc syringe I got from the farm store with a silicone hose suck on the end.



Hook up the bleeder.



Pump up the pressure to about 2bar.



Go to the SBC control unit screen and select General Servicing.



Then Replace Brake Fluid...



Again..



Next screen reminds you of the bleed sequence...



At this screen make sure your bleed hose is connected and sitting in your container so when you hit F3 you can go crack the bleeder open while the SBC builds pressure. You'll hear some valves open and close and then a burst of fluid go into the drain container. After that it slows to a steady flow and the STAR screen will basically tell you what to do next.



Here's a sample screen after I finished with the left rear caliper and moved on to the front calipers. Each of the front calipers have two bleeders - one on the outside and one on the inside. Outside one's are bled first.



Almost done...moving on to last bleeder.



There will be a couple other screens after this which are self-explanatory. After those I removed the pressure bleeder and made sure the proper amount of brake fluid was in there and closed the sytem. The last thing I did was run this pressure check where there SBC tests the system to make sure it's holding the correct amount. 90bar was factory spec if I recall and mine was 88bar so I'm good to go.



Install the plastic cover over the reservoir, shut off the ignition, start the car, check for any codes, and you're done.



I'll be flushing the coolant and changing the oil tomorrow.

Originally Posted by MK19

I'm wondering if the air in the new calipers and drained lines somehow got pressurized and that the diagnostic tool then opened a solenoid valve in the SBC module and allowed it to put pressure into the reservoir and thus expel fluid or expel air thus splashing fluid. This by the way would explain the still full reservoir as fluid from the lines would have back filled the reservoir. Another and maybe more likely possibility is that the accumulator on the SBC unit got vented back to the reservoir. In other posts, they tell us to deactivate the SBC unit via DAS before doing any brake work to depressurize the system. It doesn't sound like you did that??

I followed the above procedure this week on my '03 SL55 using Star/DAS. It went as planned EXCEPT that I never really got the gush of fluid described, and I couldn't complete each step because I was getting a message that the battery voltage was below the 11.3V required to open the solenoid valves despite the fact that DAS showed a battery voltage of between 11.7 and 11.9V. I had my 4 Amp trickle charger on it too. The lack of fluid gush suggests that the solenoids weren't opening, although I could hear valves clicking away as described above. Maybe I should have tried it with the engine running where DAS shows about 14.5 V. So, I suspect I didn't achieve a full system flush. Post flush tests for air and of the accumulator (DAS calls it a reservoir) were fine and the brakes feel as before too. Any insights here would be helpful.

Originally Posted by MK19

I'm not certain about these answers but.
1. not sure about any damage, but if so, you should get fault codes very quickly. I's drive very carefully at first and check for codes often.
2. Yes, per the above DYI, you should have had the bleeder connected.........I think it would have captured the burped fluid. In my case, I had also replaced my front pads and rotors, so the first thing I did was reactivate SBC. For that I didn't have the bleeder attached.
3. the sound you are hearing is the pump in the SBC module trying to build pressure in the accumulator. I'm guessing that theres so much air in there that it can't correctly build pressure. I'd just put the pressure bleeder on and open one or more of the bleed nipples and force some fluid through there. I believe that I saw something on DAS that said not to run a test on the accumulator more than 5 times in some time period, implying that the pump might not be able to handle it. So don't kick it on too frequently.