Train EB was applied while departing station in Auto mode. TC feedback DIR illuminated momentarily b ut no door monitor indication. Released EB - ok. Train proce eded in Auto mode to next station. ~~~~~ Fault could be duplicated in depot. Checked and found 3522 B/S cab door plunger lock nut loose. Adjusted 3522 B/S cab door sensing switch and tightened lock nut. Conducted door cyclic test nad tug test - no triggering of DIR when door is latched. All cab door and saloon doors checked ok. N.A/FAIRUZ/AZLI/FAIZAL/27.06.22