After normal start-up checks and air pressure reaches its operating range, the brake warning remains on. What should the driver do?

1. Cycle the ignition and begin the route if the warning then clears before passengers board
2. Drive the empty bus to the depot workshop because the brakes can be monitored on the way
3. Do not begin service; record and report the warning through the defect procedure
4. Begin the route after noting the warning when normal pedal pressure appears to be available