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BMW Brake Service Reminder Reset Unsuccessful
After BMW brake pads are replaced you also need to perform BMW brake service reset. When the procedure is carried out, you may not be able to reset the brake light for various reasons.
In this guide, we go over common problems that can prevent you from successfully resetting BMW brake wear reminders.
- BMW Brake Reset Unsuccessful
- BMW Brake Reset Not Possible
- BMW Brake Reset Impossible
Below we take a look at some reasons why you can not perform the BMW brake reset.
Reset BMW Brake Wear Reminder Using Hidden Menu
If resetting BMW brake pad wear using the normal reset procedure fails, try resetting using the hidden menu.
- Turn on the ignition.
- Press and hold the reset button until the hidden menu comes up. You should see FGSTNR on the cluster.
- Scroll to item 19 to unlock. It will display Lock: ON.
- Locate the VIN number on the door jamb or lower-left corner of the windshield. Add the last 5 digits of your VIN.
- Below item 19 you will see Code:00. Change Code to the sum of the last 5 digits of your VIN using the trip reset button.
- Once the hidden menu is unlocked, you will be able to reset impossible values to the factory setting.
- Turn off the ignition and wait 10 seconds.
Why BMW Brake Light won't reset
Let's say you replaced your BMW brake pads but are not able to reset the brake light.
The most issue that will prevent you from reseting BMW brake wear reminder is becasue the pads on the axle with old pads are critically well as well. For example, if you replaced the front brake pads, the rear brake pads may be low as well.
Another problem that will prevent you from restering BMW brake light is a bad brake wear sensor.
Every time you replace yoru BMW brakes, you should also replace the brake pad wear sensor.
If you keep the old brake sensor, it will be impossible to reset BMW brake light. When you carry out the procedure to reset the brake light a message will display on the instrument cluster stating "reset impossible".
If you have reset the brake service reminder for both the front and rear brake pads and the light remains on, the next step is to check the voltage going to brake pad wear sensor and read the fault codes.
Use a digital multimeter and check the DC voltage at the wires coming to the sensor. You should get between 10 to 12 volts.
Rember you are checking the line coming to the brake sensor. Not the brake sensor itself. Ignition should be on when you measure the voltage.
Read ABS/DSC Fault Codes
Use an BMW All System Scanner that can read codes stored in the DSC module memory.
Many scanners offer the capability to read and clear BMW DSC module fault codes.
Bypass BMW brake sensor
If your scan points to the brake wear sensor, replace the worn sensor.
If you have replaced the sensor but the light remains on, the next step is to bypass it and trying the reset procedure again.
Temporarily use a paper clip to short the wire that connects to the brake sensor.
Once you have shorted the circuit, carry out brake reset and read codes again.
If you are not able to reset the brake light at this point, you should troubleshoot the ABS module as it could be the culprit as well. Use a BMW scanner to read code from the DSC module.
You should check the wiring and ensure that the DSC module is working properly and can communicate with your scanner.
Published on: Tuesday, October 2, 2018.