What was found
ON TAXI OUT R DUCT PRESS READ 0, NO RESPONSE WITH POWER CHANGES. GROUNDED - YES. REMOVED AND REPLACED BLEED AIR REGULATOR REF B737-800 AMM 36-11-03-000-801/-400-801. REMOVED AND REPLACED PRECOOLER CONTROL VALVE REF AMM 36-12-02-000-801/400-801. INSTALLATION TEST GOOD. LEAK TEST GOOD. INSTALLED SERVICEABLE PRSOV REF AMM 36-11-04-00/400-801. INSTALLATION TEST GOOD. LEAK CHECK GOOD. REF TC NG-363WC-00001 FOR ACCOMPLISHMENT OF NO 2 ENG BLEED AIR SYSTEM HEALTH CHECK. ACCOMPLISHED ENG BLEED AIR CROSSOVER CK AND NO FAULTS FOUND REF AMM 36-11-00-710-801.