ODI ( OFFICE OF DEFECTS INVESTIGATION, NHTSA ) HAS RECEIVED NUMEROUS REPORTS OF ENGINE CRANKSHAFT PULLEY HARMONIC BALANCER FAILURE ON THE SUBJECT VEHICLES EQUIPPED WITH M112 OR M113 ENGINES. THE M112 SERIES IS MERCEDES-BENZ'S FIRST EVER PRODUCTION V6 ENGINE AND ITS MODULAR DESIGN ALLOWS IT TO SHARE MANY COMPONENTS, INCLUDING THE ENGINE CRANKSHAFT PULLEY HARMONIC BALANCER, WITH THE M113 SERIES V8 ENGINES. THE M112 AND M113 ENGINE CRANKSHAFT PULLEY PROVIDES ACCESSORY POWER VIA A SERPENTINE BELT. THE COMPLAINANTS ALLEGE THAT ENGINE CRANKSHAFT PULLEY FAILURE CAUSES LOSS OF POWER STEERING ASSIST WHICH MAY INCREASE THE RISK OF A CRASH. A PRELIMINARY EVALUATION HAS BEEN OPENED TO ASSESS THE SCOPE AND SAFETY CONSEQUENCES OF THE ALLEGED DEFECT.