The traffic light control boxes are all locked, but for the convenience of maintenance and maintenance, the traffic light time is also adjusted. The key of this lock is universal.

Similar to the door lock of a train bathroom, it can be opened with a universal triangle key.

However, the shape of this lock is not triangular.

It is a round shape.

Open the control box and there are several control switches inside.

By adjusting the switch, the status of the corresponding traffic light can be controlled.

Long red, long green or yellow.

The intersection of the incident was a traffic light just set last year, with surveillance video.

At that time, according to the alternate law of traffic lights, the traffic light in Lin Gang's driving direction was a normal green light.

However, the traffic light in the other direction should have changed from a green light to a red light.

However, the green light was delayed by two seconds.

It was just these two seconds that a tragedy happened.

After careful observation, there are fine dust on the switches in the control box that control traffic lights.

Very small, but obviously there is no trace of being touched.

He raised his head and looked upwards. The surveillance at the intersection was above the control box.

In other words, this control box is a blind spot in the monitoring room.

Continuing observation, Chen Yan did not miss any details.

Every switch, button, and even relay are enlarged in Chen Yan's mind.

Um?

"Brother Wang, do you have a flashlight?"

Although it is daytime, the tiny details in the control box are still difficult to see clearly.

"Yes, wait!"

Wang Min returned to the car, found an emergency flashlight, and handed it to Chen Yan: "Chen Yan, did you find something?"

Chen Yan nodded: "I'm not sure yet, I'll take a look..."

The flashlight was turned on, and some details in the control box were revealed in detail.

"Brother Wang, I have it!"

"where?"

Wang Min's face was excited, and she leaned forward and observed carefully.

But nothing was discovered.

"Brother Wang, look at this insurance."

"Insurance?"

"Yes, it's the small button in this safe box."

"The dust on this insurance button has scratches. Compared with other insurances, someone should have touched it."

"Brother Wang, has anyone touched this control box after the incident?"

Wang Min shook her head: "No, I have specifically explained that no one can touch the things inside."

"The technicians in charge of the inspection only tried it and did not touch it directly, especially the insurance button you mentioned, which was hidden in the corner, and no one had touched it."

If no one has touched it, that's good.

This shows that this insurance button is likely to be the trace left by the murderer.

"Brother Wang, notify the technicians to check if this button is pulled out, what impact will it have on the traffic light? Let's go to the Panshui Town Detective Team now."

Wang Min nodded: "I'll make arrangements now."

The Panshui Town Investigation Team is the source of everything.

Of course Chen Yan wants to go and have a look.

It takes about half an hour to go to the Panshui Town Detective Team.

On the way, Wang Min answered a call.

After hanging up, Wang Min looked at Chen Yan with a look of surprise in his eyes.
Chapter completed!