DIY: BMW Brake Pad Lining Thickness Check DIY

BMW 650i / 645Ci / E63 / E64 Brake Pad Lining Thickness Check DIY – with Pics

Disclaimer: I am not a BMW technician. This article is provided freely for entertainment purposes only and does not come with any warranty. Use the information in this article entirely at your own risk.

This DIY was created to help BMW owners quickly asses if new brake pads are required without removing the wheels. This is a visual check only and not intended to be highly accurate.

This procedure comes in handy due to the inaccuracy of the Check Control brake pad service message. In my experience the “brake service required” message is the least accurate of the several Check Control systems.

Another reason to keep an eye on pad thickness is to prevent destruction of the pad wear sensors. Once pads wear below 3mm the sensors are damaged and will require replacing at ~ $25 each. Normally the sensors can be reused if pads are replaced at or before 3mm.


A. Supplies/Tools you will need:

Flashlight
A bright LED flashlight works the best but any light will do. If you have not experienced a modern Cree-based flashlight I would suggest checking out one of these – both will far surpass the light output of a 3-cell MagLite with an incandescent bulb:
UltraFire WF-606A at DealExtreme For $17 a fraction of the size of a 3-cell Maglite and 3x brighter; I have one in every car.
Romisen MXDL RC-G2 at DealExtreme A great compact $12 Cree XR-E based light.




B. Visual Brake Pad Check

Warning: If the car has been driven prior to the inspection the rotors can easily reach 500ºF. Do not touch the brake rotors or calipers during the inspection.

1. Look through each wheel at the brake caliper using a flashlight to check pad thickness.
If you see 3mm (1/8th of an inch) or less pad remaining, you need to replace the pads. The 3mm mark is where the brake pad sensor begins to rub on the rotors and eventually the sensor is destroyed which causes the “low pads” warning light, which is different than the “brake service required” message.

3mm is approximately the thickness of the metal brake pad backing plate. If the pad material is about the same thickness as this metal plate the pads need replacing.

thanks Yorgi

any good brake pad? mine make seq. noise right now