Traffic Signal Test Cases Live Example

Test Case For Traffic Signal Test Case Template

Testing interviews often have questions for the negative and positive test cases for a traffic signal. In this post, I am jotting down some of the test cases that you can use, and also I have shared more testing test cases. If you have any questions and suggestions to improve this post then please do let me know.

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Before we write test cases for a traffic signal, let’s first understand the lights.

• Red – stop and wait before the zebra crossing line.
• Green – go.
• Yellow – stop, unless –
  1) you’ve already crossed the stop line after the green light is off.
  2) you’re so close to it that pulling up might cause an accident.
  3) You’re in the middle of the road and should move to the next side rather than going back causing a traffic problem.

Do note that traffic light has a color variation for the yellow signal. Some of the countries have that as amber or silver color. Some may even find the color difference in order. So it all depends on which standard is being followed for the traffic signal machine and country traffic rules.

You may want to adjust the traffic rules as per the rules applied in your state or country. That would make the below test cases more accurate and effective.

Traffic Signal Test Case Scenarios

• Check if the traffic lights are on during the expected traffic period as per rules.
• Check if the traffic lights timer works as per the expected specific signal.
• Check if the traffic lights are displayed in sequential order.
• Check if the traffic light for the stop signal is shown with a red light.
• Check if the traffic light for a wait unless a signal is shown with yellow or amber color.
• Check if the traffic light for the go is shown with green.
• Check if the traffic lights are one at a time.
• Check if the traffic lights during off-hours show blinking yellow or amber color displaying off for rules.
• Check the time delay between the lights.
• Check the sequence of multiple signal posts is in sync in crossroads.

What is tell negative test cases for traffic signals/lights?

I don’t know what you meant by test cases. However, I am putting down my observations on a signaling system.

• In the junction, the right of way is given in two directions, on the same track, at the same time.
• The yellow/amber lights timing is dependent on the time required for smooth braking for the maximum speed allowed, including reaction time and the time required for crossing the junction. Where is this followed?
• Visibility of signals on both sides, especially in multi-lane roads are mandatory and essential. Not so in many places.
• Pedestrians crossing gives the right of way to pedestrians over traffic if there are no signals for the crossing. Many such crossings without signals. The height in the junction, where the side road has been converted to the third lane, for a short stretch, with a median in between.

These are some of the test cases that we can use to test the traffic signal post. There are many other product-specific test cases that we can develop. I hope the test cases in this post are helpful to you. Feel free to let me know if you have any questions or comments below