Please consider upgrading the headlight harness. The Bronco light switch can barely handle the current needed to run stock headlights. Many have had the flickering Bronco headlight syndrome. The stock headlight switch definitely can't handle the current needed to run modern H4 bulbs. The way the Bronco is wired, the power runs from the battery into the dash, branches off a few times, then into the headlight switch. The headlights are then drawing power from this switch. What that means is after all the voltage drops, you end up with lower voltage at the headlights. The Night Lighter harness uses a relay system to put direct battery voltage (often 14.4 volts) directly to your headlights creating a brighter light.
Plug the harness in and the old light switch activates the new harness and the load bearing relays to bring power from the battery directly to the headlights. WH recommends adding the Night Lighter to any stock or after market wiring harness.
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