Why Does Red and Black Wire of Trailer Wiring 22114 Run to Vehicle Battery
Updated 03/01/2026 | Published 12/29/2017 >
Question:
The instructions read Route body harness black wire to positive post under hood Also says route harness red wire to positive post under hood Don’t understand?
asked by: Ken
0
Expert Reply:
I attached a diagram that shows how the trailer wiring harness # 22114 wires. The red wire runs to the positive battery terminal for powering the taillight circuits of the trailer wiring. This way all the power that the taillights of the trailer draw come from the battery and not the vehicle taillights.
The black wire is the 12 volt power accessory circuit for the 7-way which is totally separate.
expert reply by:
Jameson C
0
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Frank L.
3/1/2026
The wiring shown here for the 7 pin connector DOES NOT MATCH standard! Be sure to look up the correct standard wiring for a 7 pin trailer connector or you will be sorry when you connect your trailer.