My automatic headlights seldom work. Tonight I found out quite by accident that if I move the inside rear view mirror down, the auto lights turn on! Moving the mirror up then down about 2 inches causes the lights to quit then turn back on. Seems like a loose or partially broken wire? inside the mirror pedestal. Anyone dealt with this? New mirror or remove it to repair a wire? I thought the light sensor was on the upper forward corner of the dash. If that's not it what does that sensor do?

 

The sensor on the dash is for the AC system.

Sounds like you have a loose wire in the mirror, you will need to take it apart and see what's what! The head light sensor is actually on the windshield below the rain sensor but the control board is inside the mirror.

 

You should not have too much trouble getting to the bottom of this. First, remove the hard plastic shell around the mirror pedestal. Gently press around the seam to disengage the tabs. There is a top shell, a bottom shell and a plate/funnel to direct the light to the sensor. The sensor is on a small board, attached to the bottom shell with tabs. It should be straightforward to get all of that loose. I managed to do this without removing the overhead console, but the top shell is a bit of tight fit to release.

The memory of the exact configuration escapes me, but you might have to unhook the mirror next. There is an electrical plug on top that needs to be removed. Then the mirror can be detached by applying gentle down pressure, but while remaining parallel to the windshield. My understanding is that the metal piece attached to the glass is to remain there at all cost, as it only comes with a new windshield. Twisting of any kind is highly discouraged.

One more thing. The electrical plug behind the mirror is supposed to be secured to a metal blade of sorts. Mine had arguably already been messed with (part of a botched attempt at addressing a rain sensor issue) and was loose. You might want to spend some time understanding that blade because, best I can figure, part of its job is to also apply pressure to the back of the rain sensor, in addition to holding the electrical plug in a firm position. This blade can be bent for a proper fit.

Best of luck, keep us posted.

 

Thank you! I'll tackle it next week.

 

Just to add to FMertz' excelent instructions, take a few minutes and do a search on replacing that mirror. Plenty of threads out there because so many of us had to replace the mirror due to a manufacturer's defect.

Whether your removing it to replace because of the defect or removing to fix the sensor the intructions are the same. Here's the important point - There are a large number of stories of folks who twisted as they tried to remove the mirror from the key permanently fastened to the windshield and it cracked the windshield.

It has happend a lot more than you might guess if you do it wrong. So this is a friendly heads up.

I remember how tempting it is to twist as you try to remove it. Read a few of the stories and you'll see how to do it step by step, and how easy it is to break the window if you do it wrong mate.

Good luck with it. John