[Efthreeoh]

Originally Posted by David1

You are partially correct. Yes it is always active, but on standby. For normal braking conditions, the difference from front to rear is designed into the master cylinder and is called brake bias. EBFD controls the brake bias in heavy braking along with DSC activation. Normal driving is purely mechanical on all BMW cars. If your brakes last that long you either drive mostly highway or drive like grandma. My X5 goes through front pads and roters every 19k miles and rears every 35k miles. My 335 goes through rear pads first. My rears are good for an average 16k miles and fronts 30k+ if were to leave them on. If you "DRIVE" a BMW, you do not get even pad life. You get your brake life based on you driving style not the vehical.

Why are we comparing brake performance between an X5 vs. and E90? Two totally different vehicles. I don't drive like a grandma, I drive like a person who can achive excellent and even brake wear performance, and excellent fuel mileage, all the while driving my car like BMW intended (until they went all Lexus on us). But I don't live in a large city either, but I do drive to one every day. And I am correct about the EBFD. You are are correct the brake bias is built into the valving at the master brake cylinder, but the bias is fine tuned by the EBFD functionality programmed into the system.

[thechidz]

Originally Posted by VTECaddict

If you reset the brake service without putting in a new sensor, then it will show ------ miles and give a constant brake warning.

Is it front or rear that's giving you the -------? Maybe the mechanic accidentally reset the front brake service as well.

I believe this just happened to me. So here's the story. About 1000 miles ago I had the front brakes serviced. No problems or lights until today I get the ses light. I look on the computer and it indicates front brake service due. I go into the bc stalk menu and hit reset and now have the red brake light problem and computer is saying to service front and rear brakes now. Am I stuck with this light until I replace the sensors? Thank you

[Efthreeoh]

Originally Posted by thechidz

I believe this just happened to me. So here's the story. About 1000 miles ago I had the front brakes serviced. No problems or lights until today I get the ses light. I look on the computer and it indicates front brake service due. I go into the bc stalk menu and hit reset and now have the red brake light problem and computer is saying to service front and rear brakes now. Am I stuck with this light until I replace the sensors? Thank you

The CBS (not SES) keeps track of the front and rear brakes independently. It could be the rear brakes are now do. Also, if the front sensor wasn't replaced at the time the brakes were serviced, it would reactivate the red"Brake" light.

[PhaseP]

Unlike previous versions e90 brake sensors are two stage, meaning it has two levels of tripping. One happens somewhere in the middle of pad's life, doesn't cause CBS or dash light, only gives computer a good data point for better estimation of the remainder of miles.

If a CBS reset is tried when first stage of the sensor is tripped, but not 2nd (i.e. no dash light on) computer will look for a new sensor with no stages tripped, will see a stage one tripped sensor and will put ---- miles and brake light on. This can cleared by putting in a new sensor and reset again.

The post above about shorting the sensor leads and doing a reset is what this is. A new sensor has short circuit reading. Stage 1 tripped sensor reads 470 ohms, stage 2 tripped sensor reads open circuit.