[santo.j.graziano]

Update. With some help from a friend, the ABS unit was opened up and cleaned. I now have fluid flowing to all four lines.

 

[richardbradford]

Update. With some help from a friend, the ABS unit was opened up and cleaned. I now have fluid flowing to all four lines.

Excellent. Thanks for posting. Great to know such a clean up is possible.

 

[Michael Smith]

And a reminder to all to flush ALL brake fluid throughout the system every 2-3 years to avoid this problem developing. The higher the ambient humidity in your locale the more important this is.