Ivan, turn on motorhome ignition switch, go to trailer connector and plug in umbilical cord (mine goes from 7 pin to 6 pin but yours may be 7 pin to 7 pin or other configuration) with voltmeter test the pin connections on the unplugged end of the umbilical cord and find the pin that has 12 volt (most probably the 11:00 or 1:00 position. From there, identify the pin on the towed car that corresponds to the 12v. Take a piece of 10 gauge wire and attach one end to the corresponding pin on the towed connector. Put a piece of wire loom on the wire and feed it through an empty space to the battery. Buy an in line 20 amp auto fuse holder and fuse and attach one end to the wire and the other end to the positive terminal of the battery. Use wire ties to secure the wire in the car. Now remove the fuse, hook up the umbilical cord, turn on the ignition switch in the motorhome measure the voltage between ground and the wire at the fuse. should read 12v. If so, put the fuse back in and you are good to go. Any other questions, PM me.