After installing a supposedly new master cylinder and finding it to be poorly rebuilt and then getting an exchange, same thing again (both poorly rebuilt) I gave up and bought new M/C from a supplier in Florida that got me the right M/C for the job. While waiting for the 3rd M/C I felt that air got into the abs modulator. I looked around for the toolbox cd to bleed the system. Found one on ebay but I didn't have the proper 6 pin abs/wabco connector. Tried Kenworth shop to hook up to the abs port with their analyzer to do the bleed out. They could not make their system work
till I offered them the Wabco toolbox disc that I had. As soon as they hit the bleed button it made the pedal drop just like manually opening the bleed port. In answer to your question, I did not have any lights that stayed on or blinked.
Thus far, I am totally impressed with the 1 3/4" M/C conversion.
At 1000 mile mark I plan on posting my impressions on how it worked out. We tow a heavy toad
and old 2" M/C just wasn't getting the job done.