2018 Dodge Grand Caravan Check Engine Light: Common Problems
On 2018 Grand Caravans, the MIL most often appears due to EVAP leaks (P0456), ignition misfires (P030x), thermostat issues (P0128) or transmission requests (P0740). Scan the PCM/TCM for codes, diagnose the relevant subsystem—smoke-test EVAP, replace coils/plugs, install a new thermostat, check ATF level—and clear the MIL with a scan tool once the fault is fixed. Drive 30–50 miles afterward to reset readiness monitors.
For a full breakdown see the Grand Caravan diagnostic guide.