If all three signal lamps (white, yellow, green) flash at the same time or separately:

●   There is a malfunction on the tandem control system.

    Press the emergency stop switch.

●   The crane brakes to a stop.

    Unlock the emergency stop switch.

    Activate tandem operation. See Switching on.

If the signal lamps continue to flash:

●   The malfunction is still pending.

    Set down the joint load carefully and with as little travel movement as possible.

    Notify supervisors, co-workers and the maintenance department.

    Switch the crane off and do not use it again.

    For further troubleshooting: See Eliminating faults on the tandem control system.