SAP Upgrade from NW PI 7.1 to 7.3

Dear All,

We are upgrading SAP PI from 7.1 to 7.3 and we are getting error

Cannot
establish connection with any of the available profiles:url=BASWPITEST:50004
protocol=p4 (None); Reason:com.sap.engine.services.rmi_p4.P4IOException:
Cannot open connection to host 10.100.3.115 and port: 50004

I can see the P4 port for 50004 in Access points in SAP MMC.

Please suggest

Thanks

Jyoti