drivers side headlight is dim on 2000 astro van
It could just be a bad bulb but I would check the ground to the headlight on that side first, make sure it is clean and tight and that the connector is in good shape.
Ground is a guess. If the bulb was replaced with the wrong one is my guess #2
Check the voltage coming to the headlights. Both should be the same. If the one that is dimmer, is lower you have an electrical problem either in the grounding wire that is lose or burnt and shorted out, or in any connection coming to the bulb. If your lights are routed through a circuit board, that "may" be the problem. Check everything up to the board first before replacing that. And as stated above, it just may be your bulbs. It really sounds like a corroded or lose connection somewhere, also stated above.
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