what is the code 1345 for a mechanic?

P1345 CADILLAC - Crankshaft Position-Camshaft Position Correlation...... Possible causes - Engine mechanical condition-Valve timing off - Cam sensor or crank sensor are loose on their mounting - Faulty camshaft position sensor - Faulty crankshaft position sensor.... If this DTC started after recent internal engine repairs, inspect for proper engine mechanical timing. With the camshaft cover removed and the #1 cylinder at top dead center, make sure that the darkened chain links are lined up with the alignment marks on the exhaust and intake cam sprockets.... If a P0016 or P1345 is resetting without any engine performance concerns but the above information did not isolate a cause for the DTC, replace the Cam Phaser Actuator sprocket.