Technical Service Bulletin PIP5168A — 2012 GMC YUKON

This Preliminary Information communication provides information to the technician on the steps to diagnose and repair vehicles that may have a no crank concern. Technician will need to check the valve train for movement when the engine is cranked. If the valve train is not moving while the crankshaft is moving the front cover will need to be removed to inspect for a sheared cam sprocket locator pin. If the cam sprocket locator pin has sheared, replace the engine assembly. If the valve train is rotating during inspection, disconnect the Camshaft Position sensor and check if the engine will start. If the engine starts front cover will need to be removed to inspect for a sheared cam sprocket locator pin. If the cam sprocket locator pin has sheared, replace the engine assembly. If the engine does not start with the Camshaft Position sensor disconnected the follow published "Engine Cranks But Does Not Run" diagnosis in Service Information. Also perform an Engine Compression Test and Cylinder Leakage Test in Service Information documents all results. If the Service Information procedures above isolate an engine mechanical concern then removed to inspect for a sheared cam sprocket locator pin. If the cam sprocket locator pin has sheared, replace the engine assembly.