As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING APU GVI, FOUND THE RED BUTTON ON THE OIL FILTER INDICATOR HAS EXTENDED. GROUNDED - YES. R&R LUBE FILTER ELEMENT PER B737-900 AMM 49-91-12, BUT NO HELP. R&R OIL FILTER INDICATOR PER AMM 49-91-13. PERFORMED APU STARTING AND OPERATION PER AMM 49-11-00. OPS CHECK GOOD. NO LEAKS AND NO OTHER DEFECTS NOTED. ETOPS GROUND VERIFICATION SUCCESSFUL.