The first tests of the Sarmat ICBM is now said to be postponed until the end of 2016. The report quotes an unnamed source in the industry as saying that the reason for the delay is a problem discovered during engine firing tests. In any event, first tests will not involve actual flight - these are pop-up tests to check the silo cold start sequence.
The ministry of defense initially planned to begin Sarmat tests in 2015. That didn't happen, reportedly because of the transfer of the tests from Baykonur to Plesetsk. Since Plesetsk didn't have a silo that would be immediately ready to accept the new missile, that led to another delay - to the second half of 2016. (It is still not clear, by the way, which silo will be used for Sarmat tests.) But now the delay appears to have something to do with the missile.