I HAVE REPLACED MY REAR BRAKE ROTORS AND REAR BRAKE PADS AND BRAKE WEAR SENSOR, HOW TO RESET THE BRAKE WEAR SENSOR WARNING LIGHT ON MY BMW 520D YEAR 2012.

sometimes you need to have a garage reset it with a scanner

you need to replace the pad wear sensor when the pad wears down it wears the sensor and the sensor needs to be replace if you look at the sensor you can see the wire on the sensor wears threw

This is the brake wear indicator. When the brake pads get too thin, this sensor, which is mounted in the brake pad backing on the front left wheel and the rear right wheel, touches the rotor and wears through, grounding out the contacts and illuminating the light.
Once the light is lit, you will need to buy a new sensor as well as new brake pads. The sensor is not expensive.
First step is to examine the brake pads and determine if you need front pads or rear pads or both. Don't be surprised if you need new rotors as well as pads. Check for a significant lip at the outer edge of the rotor. If the pads have worn in the sides of the rotor more than about 1/16", you are due for rotors.
You cannot go wrong with BMW branded pads. They are safe and work great, but they are really dirty. If you want to try other brands, read the reviews. Some squeak and some fade.
I use Mexican made Brembo rotors. They work well but they rust quickly, so the brakes squeak a bit the first time you press them after washing the car or driving in the rain. More expensive rotors or BMW branded rotors don't rust so much, but they cost a lot more and don't necessarily last any longer.
After replacing the pads, turn the key to the On position and leave it on for about 90 seconds before starting the car to reset the brake pad warning light.

Study light? Do you mean warning light?
There are sensors clipped into the brake pads on the front left and rear right wheels. When the brake pads get very thin, those sensors rub on the brake rotors, and the light illuminates in the dash indicating that it is time to replace the brake pads.
The light can also illuminate if something damages the wire to the sensor. I usually replace my pads before they get down to the sensors, so I re-use my old sensors. Although the wires are fairly well secured to the suspension, after a few years, the wires can get chaffed from the wind blowing them around, and the damaged wire can turn on the warning light.

• Replace rear pads and wear sensor.
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Hold milage reset til you see test then toggle through it pro forms test and resets. Check YouTube for further info

Did you change the sensor? if you did, do a battery reset (disconnect for 10 to 20 min.).

Obviously the wear sensor has made contact with the rotor and is already damaged. You're not even suppose to resuse the wear pad sensor if its worn or damaged anyways.The way how the sensor works is that it must make contact to the rotor to complete the wear pad light indicator circuit. There is no mentioning that he replaced the the wear pad sensor with a new one.

But if one did replaced the wear pad sensor and the wear pad indicator is lit up, the way to reset it is to leave the key on in ignition switch #2 or #1 for about 30sec. turn it off and its reset.

Its possible that you forgot to replace the brake light sensors. They are about 15 bucks, and have to be replaced in order for that light to turn off. You can either get them from the dealer where they'll likely charge you 3 times as much, or you can go to http://www.turnermotorsport.com and get them there.

You have to reset the light by leaving the ignition switch on position #2 for about 30 sec. turn off the ignition and start the engine up and see if it goes out. I recommend buying a new wear pad sensor as well because now light will lit up when you're way below spec (less than 3mm)

Also, you could try with this procedure for one E39: Turning off the Check Brake Linings warning on the Instrument Cluster...
- so you've just changed the brake pads on your E39, along with the wear sensors. The old sensor(s) needed replacement cause you waited a bit too long before changing the pads, and wore through the sensor(s), turning on the BRAKE light on the dash. But wait, the light is still on? But there's a new sensor installed... what gives?!
- there is a procedure required in order to turn off the light/warning. With the ignition off, step on and hold the brake pedal. Now, while holding the brake pedal down, turn on the ignition switch to position 2 (just before cranking). Hold the brake pedal until the BRAKE light is off. Tada, the warning is gone and reset.

NOTE: This procedure worked on a 2001 E46 325i. It took about 15-20 seconds, but it cleared out w/o having to unhook the battery.

Other details find in the Owners Manual 2006-BMW-Z4m-Roadster-Owner-Manual

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As the brake pads wear, the brake pad wear sensor contained in the brake pad contacts the brake rotor. This causes the sensor to fail. When a pad wear sensor fails it opens the ground circuit of the pad wear warning light system causing the pad wear warning light to illuminate. Perform normal brake service to correct this condition and be sure to replace the brake pads with pads containing wear sensors. Once the brake pads and wear sensors are replaced, reset the brake pad warning system by turning the ignition switch to the "on" position. As long as continuity to ground exists through all the brake pad wear sensors the system should reset and the pad warning light in the dash will go out. If the pad warning light does not go out, a check of the pad warning circuit for an open circuit condition or poor ground must be performed.

i have replaced both front/ rear pads, and no matter what the dash light will not go off. I have disconnected both front/rear sensors, and light is still on , any suggestions?

I dunno if this will work on your BMW, but on my BMW Z3 and M3, it was....

Turn the ignition key to position 2, but do NOT start the car. Wait for about 45 seconds and the brake warning message will be reset.

If it doesn't reset, then the brake sensor was damage. You will need to replace the brake sensor. It sounds like you replace the brake right after you saw the warning, so the brake sensor should be okay.

Redmondeo34


A couple of things to check.
This is only if you replaced the front pads, after the warning light came on.
1. Make sure brake fluid is level and at the max mark
2. Did you replace the front pads sensors with the new pads.If not please do.
3. Check that the rear pads and sensors are not worn and do not require replacing.
4. If all above is good, Drive vehicle for about 5klm and switch off and on it will reset itself

regards
I hope this helps.