Tahoe Battery Drain

Whoa, that sounds like a real head-scratcher! Error messages, flickering lights, AND a dead battery? It's like your Tahoe is trying to send you a Morse code message of doom! You mentioned a parasitic draw – have you tried pulling fuses one by one to see if you can isolate the circuit that's sucking the life out of your battery? Also, is your alternator charging properly? A bad alternator can mimic the symptoms of a dead battery in a big way.

Good shout about the alternator. I've checked the charging voltage while the engine's running, and it seems to be within the normal range, around 14V. As for the parasitic draw, I haven't had a chance to go through the fuse-pulling exercise yet, mainly because the error codes seem to point towards the battery sensor itself being faulty. Is there any way to definitively test the battery sensor before I start chasing ghosts with the fuse box? I have access to a decent multimeter and basic diagnostic tools.

Okay, 14V suggests the alternator is probably doing its job, which narrows things down. The battery sensor... hmm. It's like trying to diagnose a headache by only looking at your toes, isn't it? You CAN test it with a multimeter, but honestly, the readings can be misleading unless you know exactly what you're looking for. Given all the symptoms and the fact that you're getting codes related to low voltage, I'd almost recommend taking it to a reputable workshop. They have the proper diagnostic equipment to pinpoint the problem quickly. It could save you a lot of time and frustration in the long run.

I appreciate the input. I took it to a local independent garage. Turns out I was right: the battery sensor was indeed defective. They replaced it, cleared the codes, and everything seems to be back to normal. Total cost was 315€ including labor. Lesson learned: sometimes it's worth paying the experts!