#621/622 found at M-car #2621,heavy air ~~~~~ #621/622 found at M-car #2621,heavy air #2621 when electrical coupler when close position no leak.When electrical coupler in couple position heavy air leak.Found bottom electrical coupler cylinder cause 5/2 v/v to leak from exhaust.Ops 20 raise to replace bottom electrical coupler cylinder. Checked by Saini/Haslan. 22/05/23 2621 to replace bottom electrical coupler cylinder Replace pheumatic cyliner and function test ok. Done by Sanip/Rizman/Koh. 23/05/23