Replacing the brake fluid in the ABS Module.

Hi Guy's. Apologies for being a pain. Can you help, I am trying to understand how you get fresh brake fluid into the ABS Module after replacing the fluid throughout the brake system. Without having to buy an electronic gadget.
I have seen / read that after replacing the fluid and ensuring there is no air in the system, you need to run the engine, activating the module, then press the brake pedal a few times ensuring that the pedal is "hard" and that's it. But how does that move the fluid through the module ? and not simply compress it ?, do you need to simultaneously bleed a caliper to allow the ABS module contents to be pushed through and replaced with new fluid.
Am I missing something ?

Hi, In a nutshell: you can't 100% bleed the modulator without a diagnostic tool cos the outlet and inlet solenoid valves must be activated in a certain sequence which is in the diagnostic's power bleed protocol. Simple as that.

sierrafery said:

Hi, In a nutshell: you can't 100% bleed the modulator without a diagnostic tool cos the outlet and inlet solenoid valves must be activated in a certain sequence which is in the diagnostic's power bleed protocol. Simple as that.

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Thanks for your reply, so straight forward, been looking at "cartoon" type moving images and module re-builds etc, and it seems there is a small volume that is only moved when the ABS is called into action. A very clever system indeed.
Cheers. Mick

@sierrafery Does this apply to the D2? I have just had to disconnect the ABS module in order to fit a repair plate on the inner wing, and then reinstated the Module. Inevitably some fluid did escape. What bleeding procedure should I follow if/as/when I get the beast running again?
Cheers

Beneagles said:

@sierrafery Does this apply to the D2? I have just had to disconnect the ABS module in order to fit a repair plate on the inner wing, and then reinstated the Module. Inevitably some fluid did escape. What bleeding procedure should I follow if/as/when I get the beast running again?
Cheers

Click to expand...

Yes it does, actually it's valid for all wabco modulators if air got into them. That's in nanocom for D2:

· Power bleed: This function opens all of the ABS valves and powers the pump
causing fluid to circulate around the system, thus removing any trapped air bubbles.

It works in short bursts every time the function is selected and you must work at the bleed nipples when it kicks in in the same way and sequence like with the pedal bleed if you see what i mean.

Excellent. Thanks for that ^

with nanocom is almost the same with some slight software difference:

sierrafery said:

with nanocom is almost the same with some slight software difference:

Click to expand...

Following the information here, I have ordered an Ancel LD700 which covers my D4 3.0L SDV6. Another e-bay buy £89, of course I could have taken it in to be done, but where's the fun (and learning) in that.
Thanks sierrafery.