Try editing the VirtualServiceEnvironmentService.vmoptions (if running as a service) or the VirtualServiceEnvironment.vmoptions (if running as CLI) and add a JVM directive.
-Djavax.net.debug=all OR -Djavax.net.debug=ssl
1. Stop the VSE service.
2. Copy or remove the vse.log
3. Start the VSE service.
4. Run the test.
5. Remove or comment the directive out and stop/start the service.
It is not a good idea to leave this directive active all the time else you will fill the logs with a lot of information.