That will tell you (as stated) where the disconnect is. Also, you probably have, but re-check your scan search settings and re-do the search.
On mine, I had issues and took it to an RV dealer when it was nearly new and paid to have it checked and rewired. No problems since. Sattelite, cable or antenna...even installed a booster on the antenna, I believe the name is Wingard, ir something, costs like $30.
These things can be tricky to find where you are not getting a direct feed, BUT, start with a direct connect and work your way backwards. Also, on mine, I have to do a SEPARATE SCAN SEARCH on each tv. Not sure if that pertains to cable, I use sattelite 95% of the time except when traveling.
Enjoy the 4th and be safe out there!