Park Ave Ultra - twilight sensor?

[MichiganJP]

2004 Park Ave Ultra.
Auto ON for night time driving not working (both headlights & dash lights). Not sure which one is the fuse for twilight sensor or if there's another way to reprogram.

Headlights work manually. Dash lights work manually. DT running lights work automatically.

Any recommended solutions?

 

[bigsky]

I could not see a fuse for the sensor looking through the list in the owner's manual. It could be the sensor itself.

The sensor is called the "Ambient Light Sensor," GM part # 914032 (new one is available on ebay). It is located in the center of the dash up toward the window, and can be pried out with a little screwdriver.

If you know someone else with a PA you could easily swap them to see if that is the problem.

 

[MichiganJP]

thanks Bigsky! gotta love the internet. there is more info here that calling GM directly

 

[Spriteman]

I'm having a hard time locating the twilight sensor on the wiring diagrams for your PA but I found this description of the twilight system and thought it might shed some light (pun intended) on your situation -

Daytime Running Lamps (DRL) and Twilight Sentinel

Twilight sentinel is a driver convenience that controls the exterior lamps in response to changes to the outside, ambient light level. The ambient light sensor is a light sensitive transistor that varies its voltage signal to the lamp control module (LCM) in response to changes to the outside, ambient light level. When the twilight switch is in ON, the LCM either turns on the DRL or turns on the low beam headlights, after a 20 second delay depending on whether daylight or low light conditions are sensed. Any function or condition that turns on the headlights will cancel the DRL operation. Battery positive voltage is supplied to the left high beam ground circuit from the LCM. When the LCM energizes the left high beam ground circuit, the current flows from the LCM switch to the left high beam. After the left high beam, the current flows through the left high beam fuse and through the right high beam fuse. The current continues through the right high beam to ground G105. Now, the high beam headlamps are in series, and split the voltage. The headlamps illuminate at half intensity. The DRL operate when the ignition switch is in the RUN position, and the parking brake is not set or the transmission is not in park. When these conditions have been met and the ambient light sensor indicates daytime conditions, the DRL will illuminate.


UPDATE

Right after I posted this message I found the wiring diagram for the headlights which includes the Twilight Sensor and the Lamp Control Module (LCM) - see attached.



From first glance I would focus on the ambient light sensor, the lamp control module and all of the related fuses at the top of the diagram. Another possibility may be a bad ground connection.

I was thinking that you could pull the ambient light sensor and jump that wire and test to see if that completes the circuit.

To access the sensor just pry/pull up on the defroster grille and then twist the sensor to remove it.

Let us know if this helps - if you can't read the diagram - PM me with your email and I will forward directly. It is much more readable in the original format.

 

[dluciemable]

I’m having a similar problem with my ‘04 Park Avenue, where is the LCM located?

 

[hogan1945]

In the center of dash by window

 

[tb.dxb]

Maybe this thread will help, including a DIY sensor replacement description.

 

[BuickGirlFromMars]

In the center of dash by windowView attachment 27622

I think he was asking where the light control module was, but good pic for sensor location. LCM to my knowledge is behind the IPC and to the right, mildy accessible under the dash but i wouldnt try to go from below