What was found
R AFT FUEL PUMP ILLUMINATED INFLIGHT. QRH COMPLETED. TROUBLESHOOT IAW FIM 28-22 FT 819 FOUND R AFT FUEL PRESSURE SWITCH REQUIRES REPLACEMENT. T/S PER FIM 28-22 FT 819 BOOST PUMP LOW PRESSURE LIGHT ON EICAS. PER STEP 48 REPLACE APPLICABLE PRESSURE SWITCH. MCC NOTIFIED. REMOVED AND REPLACED RIGHT AFT FUEL PUMP PRESSURE SWITCH IAW AMM 28-42-01. DID NOT FIX THE PROBLEM. CONTINUE T/S IAW FIM 28-22 FT 819 STEP 49. FOUND CORROSION ON D1532. REMOVED, CLEANED FROM CONNECTOR PLUG.AND SW. CHECKED FOR CONT. ALL OK. OPS CKD PRESS SW IAW 28-42-01, STILL FAILED. REMOVED AND REPLACED RH AFT BOOST PUMP IAW B767 AMM 28-22-03. OPS CHECK GOOD.