Front brakes and sensor replaced check control still on
 

Ok I just recently bought my 07 e70. The dealership replaced the front pads but did not replace the sensor. So I replaced the sensor today and everything reset. I went for a test drive and my brake light came on again as well as the replace brake pad message on I drive. Now I was able to reset the front brake warning when I changed the sensor. Everything is ok under my service requirements too. Why is my brake warning light still on and why do I have my check control message saying replace brake pads? Thanks for any help guys. Btw I love my new e70

So I came home ripped the wheel off again made sure everything was looking good. I started the car with the wheel off and no brake light warning. Put the freaking wheel back on dropped the car started it and the lights back on? What the hell??

It has to be reset with the proper tool. It was probably a used car dealership that didnt replace the sensor and they probably installed a lifetime pads :rofl:
Also you may have worn rear pads too. And if you install aftermarket sensor the light may not go away.

Makes you wonder if they checked the rotors at all or if they resurfaced them. I would check the job that they did. Check the rotor thickness and the pads at all four corners.

But guys, see his last part...what explains this?

Maybe the reason why they kept the sensor off? A short somewhere upstream of the sensor or even the connector itself?

Something goes good with with the wheel off because it acts as.it.should and goes bad when the wheel is on. I suspect a connection for brake sensor opens when you hang the wheel on? I would play wheel on and wheel off and look at stress on sensor connection. Should have to tighten lugs? Something electrical-signal changes with the wheel present and you must find that.

I am paying interested attention here because I bought a 07 x5 this month and I see it's service computer says I need to do both front and back brakes in under 5000 miles. Curious it has been saying exactly the same miles for the almost 3000 miles I have driven it. Will be checking pads maybe today.

You are.right .... if he can repeat.the problem only when hanging a wheel then he is onto a problem .... so first test this case. Then if problem still exists consider if has not been properly reset or.there is some devious explanation to bmw service not replacing the old.sensors. it is out of bmw character to not replace everything but perhaps it was the dealership money and not the customers?

If he must put back.the old sensors.and.see.if.things are.then good. Yep it.is detective time and eliminating the easiest things first is.the way to.go.

Guys! He never said it was a BMW dealer, he just said dealer. This is what he said:

So he was alerted two ways. The sensor is a two step sensor; the first changes the resistance and second is just open. It sounds like it is going to open which is probably why there is no sensor. A previous owner didn't want to pay to diagnose it or they did and didn't want to pay to fix it.

To the OP, you are going to have to check the connector as suggested in post #5 and possible the through the entire path to the module. Look at the connector first.

I bought the car from a non bmw dealer. I think they replaced the pads before the mileage was up on the sensor. I am going to play around with it again in the morning. I bought the sensors off of eBay. I'll take the wheel off again and see if it goes away again. The rotors look fine also. I inspected the pads and they are new. I will post my findings in the morning. Thanks everyone for your help

In iDrive, what does the rears say for mileage until brake service is required?

If less than 50% life left, then that might be the issue. What you might try, take the old sensor from the front, cut the wires and twist them together. Put it on the rear and reset the system again.

Ok went out this morning and the light went off. It must be something loose in the front sensor. I plan on taking it off and putting some grease on the contact points to see if that helps as wheel. The rear pads look good as well.

@ trader I went through the reset procedure through the dashboard and then went into I drive and reset the computer

OE or aftermarket sensor. Some have had issues with some aftermarket sensors in that the pins in the connector break and cause contact issues.

I would seek to find where the bad connection is. I would not band aid it with diaelectric grease. Why does connection fail when tire back on and not when off? Perhaps connection is being pulled when back on ground because the wiring isn't routed correctly. Seek to know what is wrong than fix correctly or pay more later.

This scenario happened to one of my BMW's in the past (can't remember which one). Basically, with new wear sensor, the light stayed on. Lift the car to check things and the light went off. Put the car back on the ground and the light was on. Simple answer was an internal wire break in the wires leading up to the sensor connector. With car on ground, wire would flex to the point of loosing electrical continuity. Raise the car the wire made good contact again. I was able to determine where the internal wire break was located and properly splice the wire back together.

Just food for thought.

Makes sense.to me

Hate to quote myself but after those poems here this invaluable knowledge may be lost :rofl:
In hundreds of cars I never had luck with aftermarket sensor. On E60 and E65 even some of the original sensors were not working until 2008-2009 when BMW rectified the problem. Some aftermarket companies may have followed the OEM, but i still buy only original sensors.