Low Voltage Buzzing?
 

I was recently trying to diagnose why my fuel thermosensor didn't have 5 volts, and discovered that the connector B1-20 (at least I think it was) was disconnected. I plugged this in and voila, I have 5 volts at my thermosensor! However, I also now have a super annoying constant buzz (or beep) that sounds exactly the same pitch as when you leave the lights on or open the door with the keys in the ignition.

This does not happen immediately. If I turn the key on, it happens when my battery voltage dips under 12.75 volts (even with a charger on). The battery is fine, and it is on a 6 amp charger (when I was doing this). Is there a buzzer to tell you that you haven't started the car soon enough or something?

I don't know if it matters, but I found the wire 1M at the powertrain was cut and I didn't have my soldering iron with me to fix it. The wiring diagram says that this goes to the CPU and Speedometer. Any ideas on what not having this signal would cause?

Thanks,
David

I forgot to mention, the B1-20 connector goes to the electrical load control unit. Does this help?