Installing 7-Way 4-Pole Trailer Connector # HM40975 on 2005 Ford E350 Cutaway Van Chassis

Question:

need wiring harness for 7-pin/4-pin combination trailer connector. I have a 2005 ford E-350 super duty cutaway van with 5.4 gas motor

asked by: JIM P

Expert Reply:

A cutaway van chassis is unlikely to have the wiring harness underneath for the # HM40975 you referenced to plug into. You'll need the # PK11998 pigtail, which you'd hardwire directly to the vehicle. The pigtail wire color codes are as follows:

Red - Left Turn and Stop
White - Ground
Blue - Electric Brakes
Green - Right Turn and Stop
Black - Battery
Brown - Running Lamps
Yellow - Backup Lamps

A circuit tester like part # PTW2993 would help you determine which circuit is which on the van.

The directional and running lights would tap directly into the taillight circuits. The battery circuit would attach to the positive battery terminal via a 40-amp breaker like # 9510. The electric trailer brake feed would connect to the output circuit of a brake controller.