message channelUnavailableFault
parts 
fault
element ex:ChannelUnavailable
used by 
Operation getPresentationChannel in PortType ChannelBusService
source 
<wsdl:message name="channelUnavailableFault">
  <wsdl:part name="fault" element="ex:ChannelUnavailable"/>
</wsdl:message>

WSDL documentation generated by XMLSpy WSDL Editor http://www.altova.com/xmlspy