Chrysler 2007 Pacifica - Manual (Page 340)

NOTE: Do not cut or splice wiring into the vehicles
wiring harness.
The electrical connections are all complete to the vehicle
but you must mate the harness to a trailer connector.
Refer to the following illustrations.
Towing Tips
Before setting out on a trip, practice turning, stopping
and backing the trailer in an area away from heavy
traffic.
4 - Pin Connector
7- Pin Connector
340 STARTING AND OPERATING