We present multi-frequency simultaneous VLBI radio observations of the flat spectrum radio quasar 1633+382 (4C~38.41) as part of the interferometric monitoring of gamma-ray bright active galactic nuclei (iMOGABA) program combined with additional observations in radio, optical, X-rays and $gamma-$rays carried out between the period 2012 March - 2015 August. The monitoring of this source reveals a significant long-lived increase in its activity since approximately two years in the radio bands, which correlates with a similar increase on all other bands from sub-millimeter to $gamma-$rays. A significant correlation is also found between radio fluxes and simultaneous spectral indices during this period. The study of the discrete correlation function (DCF) indicates time lags smaller than the $sim40$ days uncertainties among both radio bands and also high-energy bands, and a time lag of $sim$70 days, with $gamma-$rays leading radio. We interpret that the high-energy and radio fluxes are arising from different emitting regions, located at $1pm12$ and $40pm13$ pc from the central engine respectively.
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