A major downfall of 2nd gen Dodge pickups is the headlights on the non 98-02 sport models. They offer poor light output and beam pattern that can create dangerous driving situations in bad weather. An easy way to upgrade the lights is to convert to the quad beam headlights found on the sport package trucks while also improving the aesthetics. These lights upgrade to 9007 55/65 watt and 9004 45/65 watt bulbs over a single 9004 bulb.
I had suffered with poor headlights on my truck forever. I replaced the factory faded waffle lensed lights with aftermarket clear lensed units hoping for better light output. They did not really improve the headlight performance other than look better than the old faded lights. Additionally they always sat crooked in the fenders due to poor quality. Time for a major upgrade.
Installing Lights:
To install the new lights it is as simple as removing the bumper top cap and undoing 3 screws per light. Unplug the bulbs and pop the weather seal off the fender.
Low quality clear lensed aftermarket headlight.
Replacement sport headlight.
Comparison of sport headlight(left) vs cheap aftermarket headlight(right). Visually not a major change but the new lights sit straight in the fender.
NOTE: Pre 1998 trucks will have to have the fenders cut to allow clearance for the 2nd lightbulb in the headlight housing.
Building the Wiring Harness:
Once the headlights are installed the wiring must be upgraded to support the additional bulbs. The stock wiring is not heavy enough to simply splice into the existing harness and add a bulb socket. Relays must be installed to protect the headlight switch and not have a fire hazard. There are cheap "conversion" harnesses available online but they are not wired correctly and only utilize on bulb at a time negating the purpose of installing quad beams.
Tools:
Heat gun
Wire cutter/stripper
Automatic wire stripper
Large crimp
Small crimp tool
Scissors
Materials:
Tessa # Tape
Assorted heat shrink tubing
Assorted expandable wire sheathing
9004/9007 bulb sockets X4
Socket TPU's X4
9004/9007 connector
Socket female pins X12
Connector male pins X3
14awg ring terminal
10awg ring terminal
25 amp mini fuse
20 amp mini fuse
ISO 280 Micro relay X2
Littelfuse mini power distribution center
Littelfuse TPU's X3
Metri-pack 280 series female connectors X12
Weatherpak cavity plugs x6
Weatherpak blue seals X8
Weatherpak grey seals X16
Large splice crimps X4
Medium splice crimps X5
10awg wire
12awg wire 3 colors
14awg 2 colors
16awg 6 colors
Pinning out the Power Distribution Unit and Running Wires:
The Littelfuse power distribution box has 18 cavities that can be configured to hold a variety of fuses and relays. This harness contain 2 circuits with fused relays. 20 amp for low beam and 25 amp for high beam. I chose to put the fuses in front of the relays for easier access in the event of a popped fuse.
Knowing the locations of the relays and fuses I could start to pin in the pigtails for each circuit. Each wire gets a cavity seal and terminal crimped on. Since there are 2 circuits duplicate wire of the same color must be used. These will be joined together later. The unused cavities in the box are plugged with the weatherpak cavity plugs before the TPU's are installed.
Wiring Color Code:
Red 12awg - Battery feed
Yellow 12awg - Low beam feed
Blue 12awg - High beam feed
White 16awg - Relay trigger ground
Purple/Yellow 16awg - Low beam trigger
Red/Green 16awg - High beam trigger
With the pigtails pinned in, I could start joining wires together with the splice crimps. The 2 red 12awg wires combine into one 10awg from the battery. The yellow and blue split into two 16awg and a 14awg. The 16awg supply the passenger headlight bulbs, while the 14awg supplies the driver's side light. Additionally I pinned the female headlight connector on the trigger wires. This plugs into the existing headlight wiring to trigger the relays.
Next, I added in the black ground wires and mocked the harness in the truck to get routing figured out for wire lengths running from the passenger to driver sides. I routed the main part of the harness along with the factory harness along the bottom of the core support. With the lengths determined I started to wrap portions of the harness with the expandable sheathing. You can see the branches for each headlight bulb, trigger, battery feed, and ground.
Now that all the wire lengths were determined I could wrap the last portion of the harness and pin on the headlight bulb connectors. Ring terminals are installed on the battery feed and ground wires completing the harness.
Installation:
Below are pictures of the installed harness on the passenger and driver's side fenders. The power distribution box is attached to the fender under the ac line. The factory headlight plug is able to be tucked in the fender out of sight. On the drivers side the factory headlight plug is sealed off and tucked away in the fender. The existing ground stud is utilized for the ground on the new harness. I routed the battery wire behind the battery along the hood release cable to keep everything neat.
Final Results:
Below is a quick video demonstrating the new lights and harness in action. The factory sport trucks do not used the inner bulb on low beam. I setup my harness to use both low beam filaments for greater light output. I look forward to enjoying the improved lighting on this truck.