1972 27' overlander wiring

[emanon25]

This trailer has had the original Univolt replaced with the Univolt V. There is no power to the contol panel at the front except when the tow vehicle is connected and running. None of the electrical devices work except the water pump, also only when tow vehicle is running. Fuses are good, including the one on the negative side. There was a poor ground from the shunt to the chassis but that has been corrected.

Qestions: Are there circuit breakers? Where are the circuit breakers located? Where are the switches for the overhead vents. Can someone give me a brief summary of what each of the four fused circuits feed?

Thanks-

emanon