Dragon Launch today, but with problems

Dragon CRS-2 launched fine, but evidently had issues once on orbit.

My very limited understanding is right now it arrived on orbit with 3 of the
4 thruster pods not working.

At least 2 pods appear online now with the 3rd coming online.

They have (or will) deploy the solar panels now that 2 are online.

The questions I have a

1) Does anyone know what had happened?
2) Will this impact the ISS Berthing. I can see NASA saying "stay away until
we understand the problem"
3) Would these packs be used at all in the case of an abort of the manned
version of the Dragon?