'05 Electrical Glitch?

My '05 is having some issues. When it's wet out, the battery light goes on and off at different intervals, and the airbag comes on one day, and is off the next. This am, leaving for work, I noticed the headlights are dimming in and out. They never go off, they're just inconsistent. Am I having voltage regulation issues? Could something be cracked allowing moisture in? Not much of an electrical troubleshooter.

Truck runs fine through all of it, and there is no indication that the battery is being drained too much. It always starts fine.

Thanks for any suggestions.

 

How's the drive belt for the alt.?

 

One thing I would check is to see if water is coming in through the firewall where the wiring harness travels. I had some trouble like this on my 05 until I used some Duct tape to seal it up. There was also a small hole where a plug was missing in the front driver side wheel well. I put a nut and bolt there, and sealed up around all the wiring with duct tape and the problem has not returned.

Edit: If your are getting water in there, you may need to remove the kick panel dry all the wires and connections out and use some electrical connection cleaner on the connections to make sure you dont end up with corrosion.

 

Thanks. I should check the belt. It's been a couple of years and my AC compressor seized which probably has caused some drag on it.

Good suggestion on the firewall. I've also been getting the truck hot oil rust proofed, and perhaps the pressure from that has forced out some plug allowing water to run it, or maybe the rust proofing snuck in to a connection. Hmmm..