Bricksters, this problem is driving me nuts. Brake lights are not working. I started the standard troubleshooting and have hit a brick wall! I jumpered the brake pedal switch and replaced the bulb failure sensor with known good unit. No help. I get 12 v at the sensor (blue/red) wire ONLY if the sensor is pulled from the socket. Once I plug the sensor in, the voltage drops to zero. With the sensor out, I put 12volts on each of the wires at the sensor socket to the brake lights (Y and Y-GR) and the lights come on.

I do not understand why plugging the sensor in drops the voltage off on the sensor input wire (blue/red). Thanks in advance for your helpful suggestions.

-Phil