Headlights on in bright sunlight
Replace the sensor
Yep sounds like the sensor is no good....
Unless you have a dash cover-protector covering the 'eye' sensor. Then it 'thinks' it's always dark
Unplug the sensor and connect the two wires in the plug together, for testing purposes, with a short jumper wire. If the headlights now stay off in the "auto" setting, the sensor is bad. Low resistance across the sensor is light, so the headlights will be off, high resistance across the sensor is darkness, so the headlights will be on. HTH. -Jim
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