SAE J3190_202509

This document derives from combining the driving cycle from the European Commission’s Worldwide harmonized Light Vehicle Test Procedure (WLTP-Brake cycle) and cyclic corrosion with humidity, temperature, and salt spray from SAE J2334. This document applies to vehicles with an internal combustion engine, a rechargeable energy storage system, or both as a source for propulsion. These cycles apply to passenger and light-duty vehicles with a Gross Vehicle Weight Rating of 3500 kg or below. Before using this document for other vehicle categories, the test requestor shall assess with the test facility the WLTP’s applicability, which applies to vehicles category 1-1 (carriage of persons with not more than eight seating positions in addition to the driver) and category 2 (carriage of goods) with a fully laden mass of 3500 kg or below. Significant gaps exist in the current published procedures for evaluating the corrosion effects on brake performance during vehicle usage, primarily when the brake corner operates with corrosion exposure. The current inertia dynamometer tests published by Standard Development Organizations assess friction behavior, wear, noise, vibration, and harshness under controlled climatic conditions without the effect of prolonged corrosion exposure. Furthermore, when the brake corner is part of a regenerative braking system, newer propulsion technologies (such as those with regenerative braking and reduced use of the friction brake) can magnify the environment’s impact on the torque output of the friction brake. Lastly, the engineer has less time and fewer vehicles and field measurements during the development of the brake corner. Still, the development process must produce reliable braking systems to operate in different environments. Some procedures involve transporting the brake fixture (or brake components) from the inertia dynamometer to and from a chamber for corrosion exposure. The dismounting and transferring of the brake corner can disturb the friction couple during the test and create logistical challenges for the testing facility. This document aims to combine dynamic braking on the inertia dynamometer with cyclic corrosion. The driving schedule re-creates regular driving and soak (standstill) times, which can induce or exacerbate corrosion buildup on the brake corner.