It is known that cycle slip due to frequency selective fading causes a burst error by symbol deletion or insertion, and has a serious effect on mobile radio communication systems. In this paper, first, we show that phase rotating modulation is suitable for code synchronization error detection. Next, we consider a code synchronization controller using correlation estimator of received sequence, and the controller combines the estimator with 2π/3-shifted modulation to construct a new code synchronization error control scheme as a cycle slip cancelling system. Furthermore, we apply the scheme to the multilevel trellis coded modulation (TCM). Finally, computer simulation results confirm that proposed scheme is capable of code synchronization error correction.