My light went out in my 2003 Buick Centry and the guy say I need a dal module

You may want to repost this at rec.autos.tech alt.autos.gm is pretty much a dead group.

Could be the ambient light sensor on the dash. Could be the headlight relay in the fuse box under the hood. Could also be a blown fuse or as simple as the light bulbs failed. Next up would be a broken ground wire. Then possibly a bad BCM.

How about we start with a few tests first?

Are both high and low beams not working? On both sides?

Pull out the headlight switch to turn on the headlights. Do they come on? If yes do both High/Low beams work?

If you pull the dimmer switch up all the way (like you're dimming the lights) do the headlights come on?

If it is the BCM, it may be cheaper to buy a new car.

If your Buick is anything like my 2001, it will be falling apart soon anyway. I gave mine away after 6 years.

Nah. That car is actually an easy bypass to drop the BCM out of headlamp control. You just return to using the switch instead of the automatic lights. You do lose DRLs but unless you're in Canada they are not required anyway.