What was found
DURING PREFLIGHT, THE RIGHT SIDE FWD FUEL LOW PRESSURE LIGHT ILLUMINATED. ACFT GROUNDED. OPS CHECKED THE RIGHT SIDE FWD FUEL BOOST PUMP, OPS NORMAL IAW AMM 28-22-41. REMOVED AND REPLACED R21 GFI RELAY AND P5-2 FUEL SYS MODULE AS PRECAUTION IAW AMM 28-22-18/401, AND 28-22-43/401. PERFORMED AN OPS CHECKS FOR THE PRESS SWITCH, BOOST PUMP, GFI RELAY, AND P5-2 FUEL SYS MODULE, ALL CHECKED GOOD IAW AMM 28-42-11, 28-22-41, AND 28-22-43.