Hello all. I recently removed the factory radio from my '08 F150 and replaced it with a Kenwood DMX706S head unit. I bought the proper Scosche FD23B adapter harness to connect the unit to the factory harness, and the head unit is working just fine. However, when I remotely unlock and/or manually open the truck doors now, the dome lights no longer come on, even when it's dark outside. I matched the same color adapter harness wires to the factory harness ones but there are two adapter harness wires identified as Orange = Illumination/Dimmer, and Orange/Black = Illumination Ground/Dimmer Ground. The Orange one is connected and lights up the stereo. I have not connected the Orange/Black ground wire to anything as it does not match the color of the disconnected wires on the factory harness. There are in effect, 3 wires (if I remember correctly) on the adapter harness that remain disconnected.....one is brown and identified as Mute/Not Used (so it's not connected),one for a powered antenna/factory amplifier remote turn on (Blue ), and a third for ?????. (I don't recall its color except for the blue and brown ones). I am thinking this third wire is for the dimmer ground, but it does not match the color of the remaining factory harness wires so I'm hesitant to connect the two in case it's for something else. I wonder if there is anyone who can guide me with this. Does anyone know what that third wire is for? I don't have a schematics diagram for the factory harness so I don't know what it is for. I also don't recall what its color is. Sorry. Guess I'll have to dismantle the dash to check the colors again. Thanks.

 

Make sure you didn't just run the dimmer roller all the way down to off before you rip the dash back apart...

 

Yes, I made sure the dimmer switch was in the proper position. Oddly enough though, the dome lights came on yesterday during the daytime. Tried it again at night and again they came on. I wonder if I've got an intermittent short somewhere. If that's the case, it will be difficult to find.

 

Still having questions about the dome/courtesy light turning on or off when opening the door. As for the second orange/Black = Illumination Ground/Dimmer Ground, I've now got it connected to ground, but doesn't seem to make much difference. The dome light comes on most of the time now, but sometimes it shuts off a few seconds later, other times it stays on until the door, front or back, closes. Guess I'll have to live with it working this way.