Faultcode.
The faultcode determines if the error originates at the web service client or the Integration Service. The error can originate at the web service client if the message has the wrong structure.
Faultstring.
The faultstring provides a description of the error. The faultstring value indicates whether the error originated from the Integration Service, Web Services Hub, or Repository Service.
Detail.
The detail element contains error information that includes an error code, and the extended details element provide detailed error information when the faultstring is a Web Services Hub or Repository Service error.

<SOAP-ENV: Fault>
      <faultcode> Client/Server </faultcode>
      <faultstring>Brief Description of Error</faultstring>
      <detail>
          <ns:WSHFaultDetails xmlns:ns="www.informatica.com/wsh">
              <ErrorCode>
                 Error Code
              </ ErrorCode >
              <ExtendedDetails>
                 Actual Error
              </ ExtendedDetails >
          </ns:WSHFaultDetails>
      </detail>
</SOAP-ENV: Fault>