What exactly is an open circuit ? I used a phone charger in my car a few days ago and now some of my electrical things in my car is on the fritz. According to the manual, when the BEC unit is overloaded it will open and close a circuit. Can someone explain this or give me away to fix this ?

In "Short" you blew a fuse or a relay! :? an open circuit is when a supplied power can't complete it'* cycle.

Short = hot wire jumpered to ground wire. Generally causes high current flow, blown fuses, or, if the fuse fails to blow, fire. With a short, the connected devices see a potential of 0 (zero) volts between hot and ground, so nothing works.

Open = hot and/or ground wires have a break in the conductor. With a break in the conductor, no current flows, so the connected devices do not work.

Alright........how could I fix this :?

Easy. Tell us EXACTLY what systems are not working....which lights, accessories, etc. Most of us can tell you which circuit and what protection devices to look for. Or you can just start visually checking fuses. You have 3 fuse panels. One above the brake pedal, one on the passenger side of the firewall under the black cover labelled 'relay center' under the hood, and one above the footwell inside the car above the passenger'* feet. If you know what circuit to look for in advance from your owner'* manual (if you have one) it won't take as long! If you don't have the manual, someone (even me) can post which numbered fuses are for which circuits for you.

Well the problem is with the Left Turn signal. It turns on when I press the brake pedal. And when I'm making a left turn the blinkers blinks fast. Also I am having problems with turning on the interior lights individually. I can turn on all the lights at the same time but not individually. Does this help ? :?

Ok, got your message, and sorry for the late reply. You have some problems that are NOT related to each other.....most likely

First, I need to know what year your car is so I can look at the right schematic. I have all of them from 1986-1999, and Deathrat has even more detailed ones available for specific subsystems.

Second, I need to know if you just got the car, and it had the problems, or if they all started at different times or all at once.

I got the brake/turn signal problem, and I got the interior light thing, is there anything else? Do you have the systems monitor....the little digital car on your dash that tells you when a door is A JAR (my doors are doors, not jars).

Oops. Just checked your older posts. You have a 2001. I don't have schematics for that year, but it shouldn't matter much, 'cuz they're simple systems flaking out. Give us the other info and let'* try to get this sorted out.

I'm guessing it'* a 2002 from your user name, is that right, and if it is, have you cosidered warranty?

Feed us some more specifics, and we'll see if we can barf up a solution for you!

This is one of the main problems when a Body Control Module (BCM) is not functioning properly. I would a GM Dealer to check it out! Is your car still under warranty? :?

Deathrat nailed it before I recalled that little tidbit. No longer do we live in the day that a power supply, fuse, and switch are good enough to control electrons. We must use artificial intelligence, and run everything through a really expensive little black box.