摘要 |
A correlation is derived between a variable, defined as "virtual age", indicative of brake fluid's service age and/or mileage and the concentration of copper in the fluid. Virtual age is utilized to estimate the degree of degradation of the fluid. A reactive test strip (10) is used to measure the concentration of copper ions in the brake fluid in terms of a readily visible color change. The strip (10) is immersed in the fluid and any resulting color change is compared to a color chart (20) and a standard representative of the maximum concentration determined empirically to correspond to the desirable "virtual-age" threshold for fluid replacement. An automated embodiment of the invention includes an optical instrument to compare the color obtained from the test to a predetermined standard and determine whether a fluid change is recommended. |