Threeper

I ended up replacing the main battery, which gave me charge to attempt to start. However, developed an issue with anti-theft, which promptly killed the engine when it started. I checked every fuse, and found 18 not receiving power. Since the radio wasn't turning off, I decided to pull the radio fuse. It was fine, but once I pulled it everything else started working fine. I'm hoping it's one of two issues: Either the radio (aftermarket) is bad - I'm not sure how that would mess with the anti-theft - or my subwoofer amplifier (running 3500W audio setup) was drawing way too much power on a cold day and drained the battery. I bought an Optima Yellow Top to replace the auxiliary battery, and when I install it, will replace the radio fuse to see what happens. Will update.

For the past couple weeks, the cluster on my 03 Silverado 2500HD Duramax has been intermittently dying and coming back. Yesterday, on my way to work, same thing, only now the power windows and door locks weren't working. It wasn't until I got off work about 0200 this morning, as I was walking up to my truck, that I saw the radio was on... With the truck off and key out. Tried starting, and yeah, dead. Everytime I clicked the key over, the radio would shut off to restart, then when removing the key, the radio would turn on and remain on. I've heard multiple people, and mechanics at our shop say it could be the ignition, or fuses, batteries, or the head unit itself. Ideas?... Before I go ripping it apart and spending money I'm trying to save?...