You said the cable from the cable entry plate to the receiver.
The cable entry plate is where you connect the park cable or satellite LNB lead (not both) so in order to determine the cable is bad you HAVE to know where that is.
HOWEVER.. There may be another plate.
On many RV's there is only one cable connnection outside.. This is for Park Cable, NOT for Sattelite.. It is possible to "Re-task" it but it requires work and I personally do NOT suggest you do this.
Here is how:
You have, somewhere in the RV, either a Box of many buttons (Multi-Switch) which directs different signals to several different TV's. Park Cable, Sat, Antenna, DVD or Blue ray and more... IF you have one of these, the cable runs to the back side of the box.
The other optiona (And the cable again runs to the back side) is a wall plate, These come in 2 flavors now days.. Most likely is a wall plate with a 12 volt outlet, Switch, (The one that turns on the antenna by the way) a light and an antenna connector.. Park cable is the middle connector on the rear.
The other is a Winegard Sensar pro.. CABLE lead is labeled on the rear (Wall plate with two digital displays, 3 buttons and a column of LED lights, touching any button lights it up in most cases top one moves the LED)
The reason I do not suggest you do this:
Cable is usually el-cheapo (lowest bidder) RG-59, I have around 50 feet of it, that is equal to over 200 FEET of quality RG-6 as far as signal loss is concerned.
What I recommend: I installed nice good quality RG-6.
Someone up-thread mentioned the quality of the crimp on "F" connectors they use on these cables... HE... was understating the issues with these sneeze to remove cable ends. They are suspect #1 in a cable failure and only one time have I ever gotten to a #2 (And that was the fitting it screwed onto)
Home was where I park it. but alas the.
2005 Damon Intruder 377 Alas declared a total loss
after a semi "nicked" it. Still have the radios
Kenwood TS-2000, ICOM ID-5100, ID-51A+2, ID-880 REF030C most times