Very interesting situation you describe there. My master cylinder piston got full range work out when my rear brake line split open. Fortunately I was able add enough on my 160 mile drive home to keep air out of the system. I used the p. B. To bleed but didn’t need to use the scanner to run the abs.

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2011 E70 • N55 (me)
2012 E70 • N63 (wife)