The autopilot can be engaged by pulling the ENGAGE knob on the autopilot panel at the rear of the fuel console, and the ENGAGE mechanical indicator will show white when the autopilot is engaged. 

If the Autopilot does not engage, ensure that the autopilot POWER knob is pulled up and the POWER mechanical indicator shows white (there will be a short delay between pulling up the POWER knob and the mechanical indicator showing white whilst the autopilot gyro spins up). If the POWER mechanical indicator does not show white, the autopilot has likely been disconnected using an abnormal method, and therefore will need reset by toggling the Autopilot RESET switch on the starboard console.