School Bus Walk Gate Repairs

Mechanics Hub - March 13, 2014

Transpec Walk Gate Repair on a School Bus

Today we were working on a walk gate which is attached to the front bumper on a school bus and keeps students from running out into the street blindly. The gate makes them walk further ahead of the front of the bus where they can see oncoming traffic and vice versa.

These walk gates are a spring return and are driven by an electric motor. The one I'm working on in the video was not working. The motor needed replacement mainly because it had an overheated smell to it. It's a burnt smell that indicates the motor is starting to think about retirement into the recycle bin.

There was also a problem with the battery power to the motor. There was no voltage to the red wire in the walk gate harness. The wiring itself is very basic with one battery voltage feed, a ground and a signal voltage that comes from the stop sign wiring.

Since this bus is a Thomas bus model it came equipped with 2 circuit boards that run all of the lights and accessories. The plugs in the back route power to the appropriate this case there was no battery supply to the walk gate.

Once I replaced the circuit board the voltage was restored and the walk gate operation was back to normal. One thing about older vehicles there is no multiplexing so you can see in the video how much wiring there is. It's a real task tracing wiring because of the congestion of harnesses all bunched together.

The wiring is coded red for battery voltage, the blue is a loading lights "on" signal while the green wire is the ground. I wish manufacturers would stick to black for the ground. It makes life so much easier. Some grounds are white and I can't understand why this is the way it is which causing a lot of confusion and burned out wiring circuits.

That's why getting a hold of a wiring diagram is priceless when troubleshooting electrical problems. It's a guessing game and trying to trace wires through the maze of harnesses that are tightly along the frame and in and around the body makes it so much harder and time consuming.

With that said I hope you found this information helpful. Please comment below and add your feedback or ask a question. That's what the mechanics hub is here for to help others connect and deal with the never ending problems that exist with mechanically operated machinery.