Hello & Welcome,
You should be able to remove fuse 24 in the underhood fuse block to disable the DRLs. I do not know if this will turn off the twilight sentinel function.
I can check deeper if you want me to. Just let me know.
Take Care, Greg A.
Yes please check to see what I need to do to disable Twilight sentinel. On my '99 LeSabre, I removed the dash mounted photocell and replaced it with a resistor so that the computer always thought that there was daylight. I am hoping to avoid that procedure if possible.
Let me do some poking around in the documents and see what I can find. Hopefully it won't come down to the resistor trick, although that would probably work.
I am going to need a little more information from your vehicle.
In your glove box, there should be a sticker with some printed "Option Codes". These are usually 3 characters, and I am looking for either "CJ2" or "C67" - these are the different ways that the twilight function is implemented.
I also don't know if you have seen this in the owner's manual, or if it will do what you want it to do:
Park Lamp Override Feature
If the Twilight Sentinel lighting is active, it can be disabled by manually turning on the parking lamps. The lighting will be disabled until the ignition is moved from RUN or until the outside light level becomes daylight. The outside light level changing to daylight will cause the Twilight Sentinel feature to deactivate. The wiper-activated headlamps will override the twilight disable feature.
Please let me know about that option code.
I did some looking around, and it looks like it would be more complicated to disable the twilight function in any other way except doing the resistor trick on the sensor.
Here is some background information and the procedures to replace the sensor, just in case that is the way you want to go. There are all PDF files that you should be able to view on your computer and print.
External Lights Description
Replace Twilight Sensor
Replace Defrost Grill with HUD
Replace Defrost Grill without HUD
I hope this helps.