My 1999 XK8 has Automatic Lights marked on light switch post but they do not seem to work. The owner's manual says that the sensitivity is adjustable, and the knob is on the back of the rear-view mirror. My car does not have a knob like that. How do I know IF I have automatic lights feature and if so, how do I adjust sensitivity?

ps: I did a Search on site and entered Automatic Lights and How do I adjust automatic lights. Nothing specific came up...

 

Wayne. Back of rear view mirror: if automatic lights then there is a receded LED to detect light + a stubby black potentiometer to adjust sensitivity.

Front bottom of mirror will have a push up switch to enable auto dimming in synch with headlights on. When pressed green led lights, mirror dims if headlights on.

Its possible someone swapped a dimming auto headlights mirror with a simple one, these mirrors get replaced every 12 yrs or so from internal leaks.

If you find the LED on Back test it. Cover with masking tape, turn headlights to auto, within a minute or so headlights will be on, dashboard lites dim.

Friend dimming mirror is dimmed if button pushed.

Let us know.

John

 

I finally got out to check behind my mirror. I can only see a small circular glass lense in the recessed area. I do not see anything to adjust. Ideas, or just go back to the stone age and turn lights on and off manually?

 

Test it by trickery.

Cover the lens with black masking tape. Makes it think its night-time.
Select auto on the stalk.

Start car, view headlghts. On? Auto works. Off? Someone replaced mirror without auto lights feature.

John

 

Someone may have replaced the original mirror with a non-compatible assy.

You should have a YELLOW plug on the mirror harness with a 6 pin connector.

 

I believe the sensitivity adjuster was on the first year or 2 cars. Push the button on bottom front of rear-view mirror to turn feature on You'll see a green LED come on. Then t twist stalk to AUTO position. If the Auto On lights are not working still, try giving the corners of the mirror a little squeeze till you see the Lights On dash light come on. That works for my car. Might be a wacky soldier joint.

 

I believe the button on the bottom of mirror turns the rear-view automation on and off. I am concerned with the Automatic Headlight function. Also, I do not have a stalk on the back of mirror to adjust. A previous owner may have changed the mirror as has been suggested earlier. Still not working.

 

Wayne, is there a reason you haven't tried the test I described?

John

 

Oh, I did, nothing happened.

 

Ok so no auto headlights on this cat.

Sorry mate.

John

 

For now. I will keep researching and looking into it. I grew up in the age of having to turn your lights on and off, so I will survive...

 

Hi, the stalk I mentioned is on the steering column, not on the back of mirror. The stalk setting has to be turned to AUTO, (the settings are AUTO/ON/PARKING/OFF) as well as pushing ON the button on the mirror. I doubt anyone would change out the mirror from a non auto light car to a mirror with the function buttons. If your mirror has the button your car should have the function. If you believe it was a swap, drop the roof console overhead lights and see if mirror wiring is plugged into a wiring harness, If it is then you have the feature. A main point of fault is also in the steering column. The wiring from light stalk is sometimes broken and shorts out the AUTO setting. There is a factory zip tie on wires that holds them too tight. The other issue is inside the mirror and solder joints come loose. So a squeeze of mirror re-sits the connection. The mirror itself is a sealed unit so this issue cannot be fixed. Hope you can get it to work, it's a nice function, and option even senses rain to automatically turn on wipers.

 

The mirrors are prone to leak the electrochromatic fluid so OF COURSE the mirror might have been exchanged if the previous owner found a replacement on the cheap that did NOT have that feature.

I have a customer XJ8 in my shop with some kind of Chevy or Ford mirror probably because the electrochromatic feature failed and was too expensive to replace.

Knowing what is supposed to be installed and what is actually installed is key. These cars are OLD and who knows what people are thinking when repairs are needed.

SYBESMA'S can repair the original mirrors.