Brake Pad Wear Sensors
Fits AUDI A4 B9 (8W2, 8WC) 40 TDI
(2015)

What is a brake pad wear sensor?

A brake pad wear sensor is a part that alerts the driver of the vehicle that the brake pads are worn and require attention. When the brake pads are wearing low the sensor will trigger a brake warning light on the dashboard alerting the driver that a brake service is required.

Do I need a brake pad wear sensor?

It almost goes without saying that the brake system is one of the most important safety features on a vehicle.

Not all vehicles have a brake wear sensing feature but for those that do it is important that the sensor is working correctly. A none functioning brake pad wear sensor can cause a brake warning light to illuminate on the dash when in fact there is not an issue. In this situation if there was an issue with the brakes the warning light would not be able to notify us as it would already be illuminated.

How do I choose the correct brake pad wear sensor?

Brake parts can be one of the most incorrectly ordered parts for a vehicle. Brake systems are often uprated at the factory if a vehicle has a sports pack or some other upgrades. Some models of vehicles that are made in different countries can also have different brake system designs. In view of this there are often a number of different options listed as correct for the same model of vehicle where in fact only 1 part is correct. The factors that need to be taken into consideration when selecting the correct parts are:

• Number of electrical connectors

• Brake system manufacturer

• Brake system code. This is commonly used with German vehicle brands

• Sports pack or other factory upgrade/option

• If the vehicle has ABS or traction control

• Vehicle manufacture date (this is not the date the vehicle was registered but the date it was made

• VIN (chassis number) sequence (up to or after as specific number/letter

What brand of brake pad wear sensor should I choose?

Brands such as Bosch and TRW make brake pad wear sensors for the original car brands however they also make them for the aftermarket too. These brands are premium so the price often reflects that. There are other brands such as Apec, Borg & Beck, Febi and Quinton Hazell that also manufacture high quality brake pad wear sensors at a lower price point and in some cases with a longer warranty period than the premium brands. Which brand you choose can be down to your budget, warranty period and the brand name you feel comfortable with.

How can I tell my brake pad wear sensor needs replacing?

Wear sensors are designed to wear out and in some cases it is necessary to change them when changing the brake pads. Sometimes brake pad wear sensors fail as a result of heat that is produced by the braking process.

Safety is paramount so if you have any issues with your brake system we would always advise that you have a qualified mechanic diagnose the problem.

Here are some symptoms of a faulty brake pad wear sensor:

• Brake warning light illuminated when the pads are not wearing thin

• Brakes are squealing but there is no brake warning light on the dashboard