What was found
DURING CLIMB THE LT ENGINE CHIP DETECTOR WARNING LIGHT ILLUMINATED FOR A FEW SECONDS THEN WENT OUT. THE CREW NOTIFIED MOC AND TURNED TO GO BACK TO IAD. ON 5 MILE FINAL THE LT CHIP DETECTOR LIGHT RE-ILLUMINATED AND WOULD NOT EXTINGUISH. THE CREW FOLLOWED THE QRH AND SHUT THE AFFECTED ENGINE DOWN. A/C TAKEN OUT OF SERVICE. IAD MAINTENANCE REMOVED AND REPLACED THE LT CHIP DETECTOR. GROUND RAN LT ENGINE, NO DEFECTS NOTED OPS CHECKS GOOD. A/C RETURNED TO SERVICE.