What should you check first if the tram fails to move after switching on?
Show the correct answer
Correct answer
C. The closed door signalling device.
Explanation
The question is about a situation in which the tram does not move off after drive is switched on. The first thing to check is the door-closed signalling - answer C.
The most common cause is doors that are not fully closed. The drive lock circuit, that is the "green line", does not allow the tram to move off until all the doors are closed - it is enough for a passenger to hold one of them or for something to get stuck in a door. The door-closed warning light on the control panel will show this at once. You check the converter voltage (answer A) and the setting of the reverser (answer B) only later, because such causes happen less often, and the door warning light gives you the answer at once. Do not try to move off by switching off the lock.
Legal basis: Art. 3 para. 1 of the Road Traffic Act (Prawo o ruchu drogowym)