What was found
ON TAXI IN #1 ENG FUEL FILTER BYPASS LIGHT ILLUMINATED AND STAYED ON TILL ENG SHUTDOWN. GROUNDED - YES. REFERENCE AMM 73-11-02 FOR REMOVAL OF DRAIN PLUG & FUEL FILTER REMOVAL. REMOVED AND REPLACED #1 ENG FUEL FILTER AMM REF. 73-11-02-000-801-F00 & 73-11-02-400-801-FOO, FOUND NO DEBRIS IN OR ON REMOVED FUEL FILTER ELEMENT, REMOVED AND REPLACED FUEL DIFF PRESSURE SWITCH WITH SERVICEABLE UNIT, AMM REF. 73-34-01-000-801-FOO & 73-34-01-400-801-FOO, ALL TEST PASS OPS CK, GROUND VERIFICATION SUCCESSFUL AND #1 ENG FUEL BYPASS LIGHT IS EXTINGUISHED, LEAK CK GOOD.