Originally Posted by Todouble
What's the difference when they both land on the same neutral/ground bar in the breaker panel? Just asking?
The neutral and ground should only be bonded in the main panel or sub-panel. This is done to ensure the correct operation of any breakers should there be a short between the hot and ground on the circuits they protect. Without the bond the breakers would only protect for a short between the hot and neutral. You should never bond the neutral at the outlet or an auxiliary panel (which is what this sounds like to me without more detail).
You said you can get voltage at the inlet to the trailer but no voltage at the converter?
Do you have any type of power protection between the inlet and converter? It might be detecting a power fault and not allowing the trailer to power up.
Have you verified that the outlet is wired correctly such that the hot is going all of the way through to the correct lug on the converter? This could result in a reading of zero volts although the inlet shows voltage if you are reading the neutral and ground instead of hot and neutral on the converter.