Resolution:
Confirm that the debug enabling is off in the IcServer.srv / false in icconfig.xml.

If using non-default rv parameters set the following correctly before running the debug option:
IC_TIBRV_DAEMON=tcp:&ltdaemon_port>
IC_TIBRV_SERVICE=&ltservice_port>
IC_TIBRV_NETWORK=&ltnetwork>

To turn the debug on (file will be created at the default location i.e. logs folder / as specified in the config file):
>> ./IcDebugControl -i &ltDispatcher Name> on -icclient icdba/icdba@&ltWorkflowServerName> (Use the group name in case using FT mode)

To turn Off:
>> ./IcDebugControl -i &ltDispatcher Name> off -icclient icdba/icdba@&ltWorkflowServerName> (Use the group name in case using FT mode)

If the above doesn't work try the following:
cd $&ltWF_Server_HOME>/bin
export IC_CLIENT=icdba/icdba@&ltWF_Server_Name> (Use the group name in case using FT mode)
./IcDebugControl -i &ltDispatcher Name>  -c on -f "/tmp/icdebug.log" (Replace on with off if you want to stop the debug entries being made to the file)

How to enable dynamic debugging for the workflow server i.e. without the need to changed the config files?