| Close the shut off valve at the rear of the first trailer and open the shut off valve at the rear of the second trailer | |
| Open both shut off valves | |
| Close both shut off valves | |
| Open the shut off valve at the rear of the first trailer and close the shut off valve at the rear of the second trailer |
| Open the emergency line shut off on the rear trailer | |
| Use a calibrated air pressure gauge | |
| Open the service line shut off on the rear trailer | |
| Pull forward slowly then apply the brakes and watch for a drop in air tank psi |
| The dolly tow bar will flip up | |
| Nothing | |
| The trailers will decouple | |
| It will collapse |