TIMS showed 'obstacle detected'. TC thenoperated ODCS and proceed in ATPM back to UPD. ~~~~~ L3 3555 checked TIMS to Ostacle Detector (ODK) wire continuity - OK. Depot shunting & found fault still at 3555.  Chan GF/Alcus. 16/07/2020. L3 3555 found whenever B/s ODK wire is flexed, SIR wire tripped. Found B/s ODK wire connector loose. Need to recrimp with new connector when spare is available.  Chan SW/Hanafi. 17/07/2020. L3 3555 B/s knife connector found loose. Re-insulated & re-secured knife connector. Function test - OK.  Chan GF/Alcus. 17/07/2020.