Twilight sensor / HUD question

[junkersp11]

I have an 01 park ave ultra. Hud and headlights are always in night mode when driving. In park with the car running, I can turn it back to daytime mode by moving twilight sentinel slider on dash to off, but it goes back to night mode once I shift out of park. Is this the twilight sensor? It sounds like there is another daytime ambient light sensor or something like that from what I've read? What should I change and which sensor is it (dash location as there are 2 that look the same on each side)?
Thank you for any help guys!

 

[bluiewest1]

I think the domed sensors on the far left and right are sunlight intensity sensors. The flat one in the center is the ambient light sensor for the Twilight Sentinel system. In reading some technical info somewhere the photocell is the on/off switch for the Twilight Sentinel circuit. When mine began to act erratically, it would turn off the headlights as I passed under a streetlight. That may be an indication of a problem with the control module

On one of the GM parts sites: Sentinel Sensor part number 914032 - discontinued. There have been a few on e-Bay, but I balk at paying $50 for an item may not work

I pulled the one out of my 01 Park Ave base and noticed that the lights come on automatically when the car is running and in drive, but the headlights are on all the time. The plastic housing for the photocell is tinted blue with a tiny clear spot in the center.

Below are links to some other discussions on this site that may be helpful.


Park Ave Ultra - twilight sensor?


Twilight Sentinel malfunction