Why ISO/TS 16949 is changed with IATF 16949

Answer:
Management system standards issued by ISO, like every other standard, have a review period. The review period is around 7 years.
This standard represents mutual best practice in the field of automotive industry, as the industry is moving forward very fast standard must adapt and put the level of quality requirements higher.
There is always a transition period of 3 years, so organizations have to comply until 2019 with new IATF 16949:2016.
Organizations have to comply with the new version of the standard since the old one is not valid after the transition period. If the organization is certified against the old version of the standard (ISO/TS 164949), this certificate will not be valid anymore.

2. What is the difference?
Answer:
Like every new version, the standard has new requirements and it is following Annex SL structure.
To find out more information please feel free to look at the following materials:
- IATF 16949:2016 vs. ISO/TS 16949:2009 Matrix: https://info.advisera.com/16949academy/free-download/iatf-16949-2016-vs-iso-ts-16949-2009-matrix
- Key benefits of IATF implementation: https://advisera.com/1699academy/knowledgebase/key-benefits-of-iatf-16949-implementation/
- ISO/TS 16949:2009 vs. IATF 16949:2016 Conversion Tool: https://advisera.com/16949academy/isots-169492009-vs-iatf-169492016-conversion-tool/