Brake Flush Issues
#16
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Interestingly, my understanding is that this is just an issue with the C4 and Turbo with both ABS and Automatic Brake Differential (ABD). On the C2 cars, the pump gets flushed during the normal manual process without OBD ABS valve/pump actuation required.
May others here validate this for me?
Andy
May others here validate this for me?
Andy
My understanding is ABD is a dual circuit boosted ABS. And what happens in ABD systems is that nasty brake fluid gets trapped inside the pump and does not release unless the solenoid that controls the boosted circuit is engaged. There are two ways to fully actuate the solenoids controlling the dual boosted circuit..1) using the Bosch hammer or PTS2 2) go trigger the ABS by driving in heavy rain or snow.
Cars with normal ABS don't have this overengineered and the brake fluid is exchanged between the caliper and the pump, so you'll get all of the fluid out through normal bleeding of the brakes and clutch systems.