I_Need_Help2

Hi
about to book my w211 E270 2003 in for a D+ service knowing it needs new rear brake pads but the company (not a Merc dealer) I’m thinking of using tells me as the car has SBS braking they may not be able to change the pads as their computer may not be able to do “whatever” it needs to, to allow them to change the pads! Thus I need to take it to a Merc dealer...
Sounds a bit odd to me, what say all of you?

SZMB

You don't need to disconnect any wires or connect a computer to change the brake pads. I changed the pads & rotors in the 2004 E500 myself without disconnecting the SBC module or any wire. After changing the pads, when you first start the engine, the SBC light comes on for a second and then the car's computer resets the warning light -- that's how it happened in my car.

I_Need_Help2

thanks SZMB

vettdvr

Follow the MB procedure for changing pads w/o the startrek computer.

Also when you first energize the system depress the brake pedal so the pads will seat against the rotors.

Be sure to use NEW sensors in the pads don't try to save the $4.00 and reuse old ones.

I_Need_Help2

thanks Vettdvr, but what is the "MB procedure for changing pads w/o the startrek computer"?

Clinton Horn

There was a pretty explicit procedure for disarming the SBC pump without disconnecting it. I don't have the link but here is what worked for me.

1. Pop the hood
2. Take any key fob / keyless go devices away from the car
that is to remove the possibility of locking the doors etc. which can cause the pump to cycle.
3. Find the pump near the radiator on the driver's right side.
4. There is a large caplug electrical connection on the rear of the pump. It has a slide type locking device to keep it engaged (as I recall).
DO NOT force it off without unlocking it. The wire harness is thick and stiff. You will need some kind of non conductor to keep it disconnected from the pins. I used styrofoam but keep the trash out of it when complete.
5. Once you disconnect the wiring harness, the pump has no power and will not start.
6. You can now begin the replacement process as normal.

I have never heard of the pump self starting during removal of the caliper and potentially pinching the bejesus out of any flesh you might have in the way but it is not outside the realm of possibility. You may get an error code after you restart the car but it was only briefly (on mine). Once the pads re- seat, the system should return to normal (happy)

If you think this is too risky, try the procedure vettdvr has researched. It is kind of involved but I think it is a factory approved procedure. Mine probably is not but it has been used successfully by many on this board.

I_Need_Help2

Thanks Clinton

SZMB

Per my experience with the 2004 model and not disconnecting any wire or following any special MB procedure, after changing the pads, when you turn the key to the on position (not starting the car), you can hear the SBC pumping running, and the warning light comes on stating something like, "warning, check SBC/ABS system".... And after starting the engine, a second later, all warning lights are reset and everything is back to normal. As long as you don't get air into the system, the system should be fine.

konigstiger

Most important reason for deactivating is safety so SBC self-test is prevented as this leads to the brake pistons moving automatically.

petep86

there was another way, by putting all the windows down and locking the car, and some other steps. its somewhere around the forum

spratt22

i dont know what all the fuss is about the sbc unit ive changed front and rearbrake pads twice on my 2003 w211 320 cdi got it down to 30 mins a corner all i do is remove key make sure all doors closed and make sure no one opens them or touches key while working on car,take wheel of knock the 2 retaining pins out replace pads then replace pins job is like any other car without sbc unit.ive never had a problem with unit comming on during work i think its a bit of scare mungering by mercedes

JDM_SXE-10

I'm sure they have it figured out by now, as this thread is over 4 years old.