03 Corolla ABS flush?

[armstrhu]

Hello Forum,
Just found this place and so here goes my first post! I am wanting to flush out my brake fluid as I have about 150k and its never been done. Im going to do it myself, and I think I get the whole starting from RR and flushing out the lines progressively closer to the master cylinder. But I was wondering does this get the fluid out of the ABS system? If not, could anyone tell me where/how to get that stuff out? Also, does anyone know how much brake fluid the 03 Corolla takes during a full flush? All it says in the manual is that it takes DOT 3 but doesn't give the capacity. thanks!

[fishexpo101]

You can flush it out just like normal, won't hurt the ABS system. There isn't a diagnostic mode to open the relays internal to the ABS unit. What I've done on my previous 2003 Matrix XRS is flush the brakes with fresh fluid, then while testing them out - slam the brakes on hard enough to kick on the ABS. Then repeat the flush, if desired.

As for capacity - depends on how you flush the system and if there was any air in there to begin with. I've never used more than two little bottles (8 - 12 oz each) for maintenance related flushing (every 2 years or 30K miles) and that was even being pretty generous with the flush.

If you have a power bleeder system, might need to pick up a 32 oz bottle, as you don't want accidentally want to pick up any air. Generally, you don't want to end up with too much extra fluid around, as it doesn't store well. Even when tightly capped, it will slowly absorb moisture given enough time. Best to due flushes with fresh fluid everytime, as the interval is so long between flushes.

[armstrhu]

cool, thanks for your reply. I guess I just have one other question. So my understanding of how brakes work is that when you press on the brake pedal it puts force onto the fluid and since there is no release, the hydrologic pressure pushes a piston that squeezes the brakes. Therefore the fluid cannot circulate because if it could, you wouldn't be able to press against anything since the pressure would just circulate the fluid rather than push a piston. Now, I have absolutely no idea how an ABS system actually works, but I would think it would have to be somewhat of the same concept where the fluid has to be trapped rather than allowed to circulate. If so, would I actually be able to get the old fluid out of the abs by flushing the system then slamming on the brakes to activate the abs several times? Or am I kinda just stuck with what is in there? thanks again