EMU 521/522 Air leak test failed 1.0 Bar ~~~~~ 3521 replaced auto coupler centering device pipe & function test - OK.
#3522 B/S wiper engine union tightened & air leak stopped.
#2522 bogie 1 parking brake unit, following was isolated :
#2522 PBIC, A1/B2/B3/A4 parking brake manually released.
#3521 &#3522 STBS s/w isolated.

 Chan SW/Hanafi
09/12/2020