What causes this Error and how can I solve it? Iam not able to start nginx.

root@fuwu:~# systemctl status nginx.service
● nginx.service - Startup script for nginx service
Loaded: loaded (/lib/systemd/system/nginx.service; enabled)
Active: failed (Result: exit-code) since Tue 2017-10-24 16:35:28 CEST; 15s ago
Process: 1457 ExecStartPre=/usr/bin/test $NGINX_ENABLED = yes (code=exited, status=2)

Oct 24 16:35:28 fuwu systemd[1]: Starting Startup script for nginx service...
Oct 24 16:35:28 fuwu test[1457]: /usr/bin/test: missing argument after 'yes'
Oct 24 16:35:28 fuwu systemd[1]: nginx.service: control process exited, code=exited status=2
Oct 24 16:35:28 fuwu systemd[1]: Failed to start Startup script for nginx service.
Oct 24 16:35:28 fuwu systemd[1]: Unit nginx.service entered failed state.