Normal....Okay finally tested this
1. They do get brighter when I turn the headlights off, then dim when i turn the headlights on.
But is dependent on the setting of the dimmer. At the brightest dimmer setting, regardless of if your parking/head lamps are switched on or off, the interior control-surface/instrumentation illumination remains constant at the brightest setting. It's only from one click down (one level dimmer) that the dimming function actually goes into effect.
The control-surface/instrumentation illumination is designed in this manner so that the exterior lighting may still be engaged by the driver while at the same time still allowing for full cabin control-surface and instrumentation illumination.
For example, it's not always necessarily dimmer/darker when there's inclement weather. This allows the driver to really amp up exterior visibility for other driver while still maintaining the ability to clearly view the instrumentation and identify control surfaces.
Dimmer switch should vary the output of the climate control "rotaries" -2. but they still aren't readable during the daytime when it's sunny out - like not at all readable - not even a little bit.
3. the dimmer switch does nothing - all other lights dim or brighten - but the HVAC buttons do not.
^ Image again taken from Cars101 2006 Tribeca photo page.
The readouts "inside" the "rotary" switches should dim/brighten in accord with the setting of the vehicle exterior lamps as well as the dimmer switch.
I do not have a moonroof in my vehicle, but yes, even in bright daylight - through sunglasses, no less - the display should be easily readable.*** Can you verify:
A. that they should be readable during sunny daytime conditions? It seems like a given but I should ask.
The dimmer DOES (that's a positive/affirmation) dim the HVAC display pictured above.B. the dimmer does or does not dim the HVAC displays?