BRAKE LIGHT CIRCUIT ERROR means that the car thinks it has too much current in the brake light circuit. This comes from a switch that is mounted on the brake pedal. There are two switches mounted on the brake pedal, and I am not sure which one causes the error.
If the message is LEFT BRAKE LIGHT OUT (or equivelent) then the left brake light is not working. If the right brake light is not working, then the message will be clear. If the brake light is really working, then the ground for the light(s) on the particular corner may not be connected well. Unplug the light assembly and check the condition of the pins. You would do well to completely remove the lamp housings, 4 screws, and inspect the intergrity of the plastic.
The BRAKE LIGHT CIRCUIT ERROR message remains on until the car is switched off, then the message may or may not return when the brake pedal is pressed. My car can give the message, and I can switch the car off then back on again, and the message goes away and does not return for several days, or weeks. I have been struggling with this for going on three years now, and the measage is very intermittant.