Wiring Harness Options and Installation on a 2003 Chevrolet Express Van

Question:

2002 wiring harness does not have a direct connection to the battery? Does it need on because I can not get it to work. 2003 shows both wiring harnesses, which one is correct?

asked by: John

Expert Reply:

There are two trailer wiring harnesses available for your 2003 Chevrolet Express Van if it does not have a factory installed wiring harness. The Hopkins Plug-N-Tow Wiring Harness, # 31345, that you referenced does require the red wire from the input side of the converter box to be ran to the vehicle battery using the included extension wire and inline fuse to work (see photo). The power wire provides power to the converter box which powers the trailer lights. I have provided a link to an article on tips for routing a power wire.

The other option is the Tow Ready Trailer Wiring Harness, # 118392, which does not use a converter box. This wiring harness draws power directly from the vehicles tail light circuits. The installation of this wiring harness is easier than the Hopkins wiring harness simply because it does not require you to route a power wire to the battery, but this wiring harness leaves your vehicles sensitive electrical system vulnerable to dangerous short circuit and mis-wire situations from the trailer.

The powered converter box on the Hopkins wiring harness also acts as circuit protection for your vehicles electrical system by preventing power from back feeding onto the vehicle wiring.

I have attached installation videos of both wiring harnesses for you to check out.

expert reply by: John H