As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ON TAXI OUT, #1 OIL FILTER BYPASS LIGHT FLASHED & THEN STAYED STEADY, EXTINGUISHED AFTER 5-10 SEC. 5 MIN LATER IT HAPPENED AGAIN - SAME RESULT - LIGHT EXTINGUISHED. GROUNDED - YES. CHECKED FMC FOR ENG 1 FAULT MSG, NO MSG. REMOVED & REPLACED ENG 1 FUEL FILTER REF B737-800 AMM 73-11-02. REMOVED & REPLACED ENG 1 FUEL FILTER DIFF PRESS SW REF B737-800 AMM 73-34-01. RAN ENG 1 & LIGHT NEVER CAME ON.