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Q: interior lights stay on on 1999 Mercury Grand Marquis

why do the interior lights in my 1999 mercury grand marquis suddenly stay on all the time. The head lights do not seem to come on for the auto lamp system either.
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The interior lights are likely on due to a faulty door ajar switch. Have this system checked - the car may think a door is open, keeping your interior lights on.
Your interior lights stay on because of a malfunction with the light module(cost $400.Ford has a better idea)wasn't it great when we had those switches in the door post that shut them off.I pulled the bulbs from the floor lights and the doom light.I'm going to find the wires for the dome light in the ceiling and put a toggle switch on it.
The switches are still there, however they are with the latch instead now.

The module is not likely at fault.
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