One problem related to check engine light on has been reported for the 2004 Mercedes Benz ML500. The most recently reported issues are listed below.
This could be related to a software problem in all ml class. 1. Obd system cause the check engine light to illuminate incorrectly 2. Stuck fuel-level sensor cause to report incorrectly 3. The speedometer out of tolerance is reporting incorrectly 4. Obd system is reporting incorrectly causing faults in systems.