I have a 97 grand Marquis! At night when my lights are on they will start blinking off and on! Even my dashboard lights! They all blink off and on at the same time! What is that! How can I fix it!!!
It's most likely the lighting control module. They were very troublesome. HTH. -Jim
Try headlight switch or try using them manually you didn't say weather you tried them manually does it do the same thing manually if it does I would say it's the lighting control module like Jim said. You could also have a bad ground somewhere on the headlight circuit.
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