DT548 UNDERSHOOT ECK BCP FOR TIMING 0716HRS, 1941HRS ON 080221, ABNORMALITIES DETECTEDBCPs ON BOTH DT547 AND 548, SIGNALS CHECKED AND FOUND NO NORMALITIES AND CLEARED ON SIGNAL SIDE ~~~~~ DT548 UNDERSHOOT Check and found #3547 ACU leak at exhaust port.Replaced and function brake test ok. ACU-Old s/n: 1024-006  New s/n: 1236-040 Not: 2247264 raise. Done by Faddzal. 09/02/21