One problem related to check engine light on has been reported for the 2003 Chrysler 300M. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2003 Chrysler 300M based on all problems reported for the 2003 300M.
Check engine light came on while driving. Engine started hesitating at random times. Code readout indicated failure of cam shaft position sensor. When this was repaired, mechanic stated that codes were also present indicating failure of catalytic converters (1 per exhaust line). These should not fail during normal use.