I have shutdown the ASA SSM module with
hw-module module 1 shutdown
How can I power it on again.
Hardware reset means the ASA SSM module will actually reboot itself rather than just reload the software.
You can't use "hw-module module 1 reload" because the SSM module needs to be up for this command to take effect. As you have shut the module down it won't respond to the reload option.
A reset does not set the config back to default or anything. What a reset does is simply a shutdown followed by a restart.