Originally Posted by JonathanGennick
Was well after dark both times. I suppose parking-lot lighting could have been different though. First was out back in the Target parking lot. Dome light stayed off. Later was in the Culver's parking lot, where the dome light did light up. Was the Culver's parking lot not as well lit as Target's? Possibly. I would need to go back and look to be sure.
Is there really an ambient light sensor trying to second-guess the dome light? I don't recall reading about that in the manual. Kind of a silly thing, imho. I'd rather have the predictability.
The ambient light sensor controls the auto lamps as well as other lighting within the vehicle.
Per page 126 of the fifth printing of the 2012 Ford Focus Owner's guide
Ambient lighting (if equipped)
Illuminates the interior with a choice of several colors. The
ambient lighting control switch is located in the overhead console.
• Rotate the control knob past the first detent to activate and adjust
to the desired brightness.
• Press the left color pallet switch to cycle through the color
• Press the right search mode switch to activate all dome lamps and all
ambient lighting. Press the search mode switch again to deactivate the
dome lamps and return the ambient lighting to the previously selected
The ambient lights come on whenever the ignition is in the on position,
the headlamps are on and the outside ambient light level is low.
Note: The ambient lights will stay on until the ignition is placed in the
off position and the vehicle is locked or the accessory delay timer
The interior lamps and select exterior lamps illuminate when the remote
entry system is used to unlock the door(s).
The illuminated entry system will turn off the lights if:
• the ignition is on,
• the remote transmitter lock control is pressed, or
• after 25 seconds of illumination.
The lights will not turn off if:
• they have been turned on with the dimmer control, or
• any door is open.
Basically its more complicated than just on or off.