Mike Green9

Hi.

Last winter I installed a Kenwood DNX890HD on my 2008 otherwise stock C6. I like this unit – more on this in a later post.

A couple of weeks ago, I noticed that every once in a while the headlights would come on during the day, even bright sunny days. After a short while, say 20 minutes, they would shut off and all would be normal. The headlights work just fine at night.

I suspect the twilight photo cell sensor on the dash is developing a problem. I tried covering the photo cell with a rag – and yes the lights do come on as expected. Removing the rag, and they do shut off.

I hooked up the 'dash lights on' sensor from the Kenwood to the F55 switch on the console. I'm just wondering if this could be causing the problem. Note that all worked perfect until a couple of weeks ago. Have any of you experienced a similar problem?

Thanks,

M...

markcz

Stranger things have happened, but the photoeye sensor circuit and the dimmer circuit that you tapped aren't the same one, so that's probably not your problem.

Pop out the grill and make sure there isn't an obvious issue with a pinched wire or loose plug to the sensor.

Mike Green9

Thanks Mark.

I will check the connection. If I don't see an obvious problem, I'll bite the bullet and try a replacement photo eye.

I'll keep you posted.

M....

Mike Green9

Hi.

The problem was in fact the photo sensor. It's resistance varied considerably under a constant bright light, thus giving erroneous readings to the BCM.

I temporarily swapped out the photo cell with a miniature toggle switch and a couple of resistors, mounted in the same hole in the dash speaker plate. Flipping the switch forward simulates daylight, flipping the switch back simulates night. Works like a charm.

In Canada, headlights are forced on at dusk – you can't shut them off until you shut the engine off. I don't like this since they always come on way too early when it is still quite bright out, and they always come on when I fire up in my garage.

Now I have to decide if I want to buy a new photo cell from GM (About $30), or stay with my new setup.

Thanks for your input.


M...

markcz

How about buying a new sensor AND wiring in a switch. Turn the switch on and it works like oem, turn the switch off and the lights stay off

Mike Green9

Great idea from a great mind.

Problem is I don't want to drill any new holes in the dash speaker grate to accommodate both the oem sensor and my switch. I could start running wires but then I would have to remove the console and I'm getting lazy in my old age.

Thanks again,

M...