Make sure you have enough fuel in your fuel tank.
Most RV generators stop running if the fuel tank is not at least half full. This is to prevent the RV from using its' entire fuel supply.
Check the fuel gauge to make sure that the tank is at least half full.
Add fuel if there is not enough.
Inspect the exhaust system.
This is under the RV.
To make sure that you inspect all components of the exhaust system, consult your RV's manual for a detailed description of where to look.
Check for surface damage to the exhaust system.
Check for oil and fuel leaks.
Gently pull on the exhaust system to confirm that it is securely attached to the RV.
If there is any damage to the exhaust system, have a RV mechanic repair it.
Inspect and clean the wire lines.
Consult your RV's manual for the locations of all wire lines.
Check them for corrosion, rust, and other debris.
Use an air pump to dislodge any materials that are stuck between the wires. This can be purchased at a camping supply store.
Check the oil level in the RV.
If the oil pressure drops below a certain point, some generators have a sensor that will turn the generator off.
Consult your RV's manual for how to check the oil.
If the oil level is below the recommended amount for your RV, add enough oil to meet the recommended amount.
Press the start button so that the generator will not bypass the oil pressure cut off circuit. Consult your RV's manual for the location of this button.
Verify that the sensor wire has not been damaged. Consult your RV's manual for its' location.
Change the oil and filter (optional).
Check your RV's manual for the recommended service schedule for oil and filter changes. If it is past due, this should be completed.
Change the oil and filters if you know how to do so or have a RV mechanic do it.
Run the generator for 10 seconds and turn it off.
Inspect the generator for oil leaks or wipe it with a white cloth.
If oil is leaking from the generator, have it repaired.
Test your RV generator.
Turn the generator on and observe its' performance.
After completing these steps, the RV generator should function properly. If it still does not work properly, have a RV mechanic evaluate it.