I have an 04 530 it's a great car but it has a few small problems. The most annoying is a horrible screetching sound inside the car when you 1st start it. It goes away usually after a minute or two, sometimes it says until you shut the car off and turn it back on. Perhaps some sort of relay or bad fan behind the dash? The blower control makes no difference so I doubt it's a fan. Thoughts?
As long as it's not your wife, I wouldn't sweat it too much. Have you checked anything under the hood? Popped the hood, stood over the engine (might be a good idea to not dangle your angora scarf around your neck as you lean over the engine bay and fan) and listened when you've started it up to pinpoint the area the noise might be coming from? Have you checked your power steering fluid level? Looked for any obvious leaks? Checked the tightness of any accessory belts? Maybe it has just a single serpentine belt... maintenance history? When was the last time belt(s) were changed? Water Pump? Air conditioning compressor? There's a lot of possibilities, and even remotely helping via remote armchair speculation isn't going to go very far unless you narrow it down a bit.
2005 BMW 530i (wife's car) had this identical problem. Independent BMW Repair shop replaced a fan in the dashboard. Screeching sound at startup is now completely gone!
