If you can get to it, check the cable's F connector at the satellite dish, as well as in back of the modem. It should be finger tight.
You might also want to visually inspect the cable for any splits, nicks, or any kind of inner cable exposure wherever it's possible.
This is about as much as you can do. Only other thing is to replace the radio and/or modem if it's a hardware fault, but you will need a tech visit for that.
This will notify any of the admins when they come in on Monday morning:
Good morning Mike,
I see it's your first post here, so welcome to the community! I pulled up your account to investigate and even I can't reach your modem to run diagnostics. We have decided as a courtesy to dispatch a technician to do a complete review of your site due to the concerns you've been encountering. Your dispatch is currently scheduled for our earliest available slot: Monday, Nov 26, 2018 between 11:00 AM-02:00 PM. Call us at 866.347.3292 and reference case #116802530 if you need to reschedule. Please let us know how the site visit goes.
Good morning Mike,
Glad to see the site visit was completed last week. If you have any other concerns, don't hesitate to drop by the community again, we're here to help! Have a great weekend!