^^^lout.... Occupation mechanic since 1988^^^^
if brake fluid has water in it
, it needs flushing
and then it will have 0 percent water
or does it need bleeding?
i'm not sure anymore
i normally flush the brakes every couple of years and perform an abs bleed/flush on any vehicle i havent worked on before or every second change of fluid and anytime the system has been open to air and as mentioned an appropriate scan tool is required
flushed and then bleed
Different FSM and one RM:
Basically from several Technical Servicing informational sources:
Some ABS devices have their own internal reservoirs (Bosch ABS5.3, for example) that are not a part of the primary brake circuit and are only opened to the rest of the circuit when the ABS is active. Now, if you just bled your system as soon as the ABS cycled - even for a few tenths of a second - the "old" fluid (which was never bled because it was hidden) would be dumped into the primary circuit. Not the end of the world, but you want fresh fluid everywhere, right?
Most better quality Auto Service Centers use the TEST stripes as I use and have pictured and recommended to use on this thread to do a sample checking of your brake fluid .
Another source that uses and recomends the TEST strips.
How do you know when it’s time for a brake fluid flush? Visually check the fluid to see how translucent — or how black — it is. And then use test strips, which measures the moisture content in your brake fluid.
reasons why you should flush your brake fluid
.... periodically flushing
brake fluid to remove dirty, contaminated fluid from the system, especially on today’s vehicles with ABS and traction control.
Here’s why you should flush your brake fluid:
Brake fluid is “hygroscopic,” which means it actively attracts moisture from the air. This is often touted as the main reason to change your brake fluid. Because many parts of your braking system are made of metal, flushing the brake fluid can prevent corrosion and failure of those metal components.
As brake fluid ages and becomes contaminated with small particles, the boiling point of the fluid goes down. This reduces your braking performance, which you might not notice for awhile, but every inch counts when it comes to braking. In extreme cases, it can lead to the brakes not working at all.
As your ABS and traction control systems activate, they generate heat, which further breaks down the fluid.
Anti-lock braking (ABS) and traction control components are sensitive to moisture and small particulates from contaminated fluid. We recommend flushing the fluid before it can damage these pricey parts. An ABS module, for example, usually costs several hundred dollars.
While I would say that a complete flushing and brake fluid replacement is the best service for an ABS system a periodic basic fluid replacement at the brake master cylinder and then bleeding the complete system at the calipers is better then no service at all.