In about two weeks, most kids in southeastern Wisconsin will jump on a bus and head back to school.

CBS 58’s Jessica Tighe got an inside look at how the state makes sure those buses are safe.

“So he'll turn all the lights on. High beams. Turn signal," Inspector Harman Chahal with the Wisconsin State Patrol announced as she started her first inspection of the day.

There’s a lot to examine on each bus and a lot of buses to check. In fact, there are more than 1,500 school buses in southeastern Wisconsin alone.

Inspectors will the State Patrol check every bus in the state at least once a year. In most cases, the checks happen before the school year starts.

“The reason why the Wisconsin State Patrol comes to do these inspections is because we have the most valuable commodity in these buses,” Chahal said.

Inspectors start with the outside of the bus. They check the lights first.

This year, for the first time, they’re also making sure buses built after 2004 have amber lights. That’s now a state requirement. The amber lights are a warning to other drivers on the road that a bus is getting ready to stop and will soon activate the red warning lights. Drivers can pass when the amber lights are on if it’s safe to do so.

Once the lights are checked, inspectors move on to the tires, the mirrors, and the door.

"The biggest issues we have aren't because mechanics aren't taking care of their buses, it's just because buses get used and issues come up as you use the bus,” Chahal explained.

A really common issue discovered deals with the emergency exits. The buzzers go bad. In this case, the buzzer was working.

Chahal also made sure the emergency door had visible lettering on the outside that states, “Stop on flashing red.” That’s also a new requirement this year. In the past, the door lettering simply stated “emergency exit.”

Eventually Chahal made her way to the hood.

Once inspectors pop the hood, they look for any problems that might cause the bus to break down. Chahal said serious issues are rare, especially when dealing with big bus companies, but they do uncover problems.

"Issues come up when we deal with charter schools because they have maybe five or 10 buses and have one person working on them. They have older buses," Chahal said.

Older bus or newer bus, they each undergo the same check.

Inspectors even slide underneath the bus. They roll from front to back and carefully look at components that are essential to safety on the roads, equipment like the brakes and springs.

The inside of the bus needs to be examined too. Seat cushions must be secure-- no rips either. Any graffiti has to be gone.

Violations are noted and need to be fixed before the bus can go out.

"Sometimes it's a small issue that they can fix right away. Then I can check it again and make sure that it's good to go and approve the bus. Sometimes it's bigger issues that take awhile, like leaf springs that are cracked. That's not something they can immediately fix,” Chahal explained.

In a case like a broken leaf spring, the bus is put out of service and the company has five days to fix the violation. The inspector then returns and reexamines the bus. It won't hit the streets unless that issue is resolved.

State inspectors also do “spot” checks throughout the year. They’ll show up at schools or pull over buses when the drivers aren’t expecting it. Those checks often focus on carriers who repeatedly have issues. The Wisconsin State Patrol can also fine those companies.

“If we consistently have a problem with a carrier, we do take more action,” Chahal said.

CBS 58 asked for specific numbers on how many buses in southeastern Wisconsin failed inspection last year. The State Patrol couldn’t give us that information because it has each inspector keep his or her own reports. They’re not centrally located. The state is now in the midst of changing that system so the numbers will be available in the future.