Train jerked intermittently when arriving station (braking/accelerating). TC feedback powering off i ntermittently at car 1678. ~~~~~ Check and found #1678-A2 CCD fuse blown-replaced ok. Check terminal no sign of flashover. #1678-A1 CCD shoe flashover-replace ok. Further check line breaker/INV/BCH/Brake resistor ok. Surge Arrestor meggering test ok. A1 & B1 CCD height fail at lower limit (197~198). Adjusted to (202~203) ok. To be further monitoring.    Done by Sanip. 14/07/21.