Pinpoint Test D: Premature/Uneven Brake Pad Wear

D1: PREMATURE/UNEVEN BRAKE PAD WEAR INITIAL CHECK
1. Assess which set of brake pads have worn prematurely or unevenly.
  Is there a metallic grinding noise coming from the front or rear brakes and/or the brake pad wear sensor indicator is illuminated on the Instrument Cluster (IC)?
  
  Yes: Disassemble the affected brake caliper assembly. Clean abutments and slide pins and apply fresh grease. Reassemble the brake caliper and replace brake pads as required, making sure the brake pads move freely in the caliper(s).
  
  No: Raise a TA with attached pictures of the brake with a concern.

Brake Disc Corrosion Inspection

NOTE:

Jaguar Land Rover braking systems are designed to achieve peak performance under a broad range of driving conditions. Jaguar Land Rover's priority is the safety of its braking systems, and they are designed to perform in all circumstances, however the brake may, dependent on the environment and driving style, produce the occasional noise. This does not impair the operation or performance. Brake noise is an issue facing many vehicle manufacturers and Jaguar Land Rover are constantly working in conjunction with the leading brake caliper and brake pad suppliers to develop design solutions which reduce brake squeal noises.
Jaguar Land Rover Limited offers no warranty and is not responsible for any repair or replacement to the vehicle, part or accessory that is required as a direct result of: Normal wear and tear this includes brake pads, brake discs, and any other friction related components. The list is not exhaustive. Defects or damage caused as a result of the vehicle being used in motor sport events, or for any purpose other than normal, private, or commercial use. Brake pads, brake discs, and any other friction related components are covered against manufacturing defects for the duration of the manufacturer's warranty.
Most JLR brake pads now utilize NAO brake pad friction material technology. This creates a 'transfer layer' on the brake disc, whereas previous brake pads use an abrasive friction mechanism, which leads to greater pad and disc wear. This NAO transfer layer has a dull metallic appearance.
However, some situations with low brake usage, or through the use of non-JLR approved wheel cleaners, can lead to a build up of surface corrosion on the disc (see guidance below and in the appropriate service information) - this surface corrosion build-up does not adversely affect brake performance.

	EXAMPLE IMAGES	DESCRIPTION
1.	Courtesy of JAGUAR LAND ROVER NORTH AMERICA, LLC	NOTE: If the brake disc(s) is similar to illustration E245239, This is not a manufacturing defect and is not covered under warranty. Light corrosion - If the disc(s) condition is as illustrated and within the service wear limit Refer to: SPECIFICATIONS . This is not detrimental to braking performance and brake disc replacement is not required.
2.	Courtesy of JAGUAR LAND ROVER NORTH AMERICA, LLC	NOTE: If the brake disc(s) is similar to illustration E245550, This is not a manufacturing defect and is not covered under warranty. Light corrosion - If the disc(s) condition is as illustrated and within the service wear limit Refer to: SPECIFICATIONS . This is not detrimental to braking performance and brake disc replacement is not required.
3.	Courtesy of JAGUAR LAND ROVER NORTH AMERICA, LLC	NOTE: If the brake disc(s) is similar to illustration E245238, This is not a manufacturing defect and is not covered under warranty. Moderate corrosion - If the disc(s) condition is as illustrated and within the service wear limit Refer to: SPECIFICATIONS . This is not detrimental to braking performance and brake disc replacement is not required.
4.	Courtesy of JAGUAR LAND ROVER NORTH AMERICA, LLC	NOTE: If the brake disc(s) is similar to illustration E245551, This is not a manufacturing defect and is not covered under warranty. Uneven corrosion with pitting - If the disc(s) condition is as illustrated and within the service wear limit Refer to: SPECIFICATIONS . This is not detrimental to braking performance and brake disc replacement is not required.
5.	Courtesy of JAGUAR LAND ROVER NORTH AMERICA, LLC	NOTE: If the brake disc(s) is similar to illustration E245552, This is not a manufacturing defect and is not covered under warranty. Uneven corrosion with pitting - If the disc(s) condition is as illustrated and within the service wear limit Refer to: SPECIFICATIONS . This is not detrimental to braking performance and brake disc replacement is not required.
6.	Courtesy of JAGUAR LAND ROVER NORTH AMERICA, LLC	Brake pad to brake disc surface contact area measurement instruction Section (A) is 100% of the brake disc working surface. To workout 30% section (B) of the brake disc working surface follow the below steps. Step 1. Measure section (A) of the brake disc working surface. Example 60 mm. Step 2. Divide the measurement from step 1 by 100. Example 60 mm ÷ 100 = 0.6 mm. Step 3. Multiply the total of step 2 by 30. Example 0.6 mm x 30 = 18 mm Step 4. This will give 30% section (B) of the brake disc working surface. Example 18 mm.
7.	Courtesy of JAGUAR LAND ROVER NORTH AMERICA, LLC	NOTE: If the brake disc(s) is similar to illustration E245240, This is not a manufacturing defect and is not covered under warranty. Heavy pitting with corrosion - It is not necessary to replace the disc unless the corroded region covers more than 30% of the brake disc working surface.
8.	Courtesy of JAGUAR LAND ROVER NORTH AMERICA, LLC	NOTE: Brake discs are recommended to be replaced in axle sets. Severe pitting and corrosion - If the disc(s) condition is similar to the illustration. Replace the brake discs.
9.	Courtesy of JAGUAR LAND ROVER NORTH AMERICA, LLCJAGUAR LAND ROVER NORTH AMERICA, LLC Courtesy of JAGUAR LAND ROVER NORTH AMERICA, LLCJAGUAR LAND ROVER NORTH AMERICA, LLC	NOTE: The use of non-JLR approved wheel cleaners can cause accelerated corrosion of the brake disc. Use of non-JLR wheel cleaners - Evidence of use of non-JLR approved cleaners may be indicated where discoloration/corrosion of brake caliper/springs occurs. SSM73952 And SSM73953 - Brake Caliper Discoloration - provides guidance to use of wheel cleaners. The pictures shown illustrate typical calipers on vehicles that are corroded due to using unsuitable cleaning agents Corroded calipers, due to using unsuitable cleaning agents, are NOT covered by warranty.