I have an 85 4x4 truck with one dim headlight. I tried replacing the light and recepticle to no avail. Is it a faulty ground somewhere?
Make sure both headlights are the correct ones and the correct wattage. That sounds like corrosion or a bad electrical connection. Clean all the connectors and see if that helps. If the aim on a headlight is off it can appear dimmer when it is not.
Like I said, new connector (corrosion/connection problem solved) Aiming is not a problem. Its somewhere in the ground system I think.
Check the fuses under the hood. Mine was running dim without a fuse even in it.
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