Trailer lights not working

[Jamieballiett]

I recently bought a 2008 Jayco 1207.
I have been unable to get the trailer lights to work. I have a 2005 Volvo XC70 with a 4 pin trailer hitch and the Jayco is a 7 pin factory connector. I purchased two different 7 to 4 pin connectors and neither works. One is just a seven to 4 pin and the other is a 7 to 4 with a separate ground and wires for battery and brakes.
I know the Volvo setup is working because I connected it to my 4 pin boat wires and all the lights work.
I know the Jayco 7 pin connector works because when the popup was delivered, the lights were all working.

I did the following steps to try and get the lights to work.
Put the pop up on the Volvo hitch, chains and all.
Connected the 7 pin with the basic 4 pin (didn't work) and then tried the 7 pin to the more advanced 4 pin AND also connected the ground to the volvo hitch with a screw. Nothing happened!

Am I missing something? Does the black wire need to be connected to run the lights from the Volvo battery? Is the basic four pin not enough power to run them? There are electric brakes on the pop up but we are not going to use them.

Thanks for any help!

[chrisb]

Try hooking it up and driving around the block. Sometimes you have to make a good ground