i have a vr 93 model calais and when i put my foot on the brake the low beams turn on and the gear selecter light but they will not stay on from the switch this car is a project it was rear ended and has had parts removed im sure im missing module of some sort located just above the fuses also the power windows dont work or the key remote it has got the body control and i have checked all the fuses/relays and still no idea please some one HELP!!!!!!
if the car has had a rear end it sounds like you will have a brake light wire & park light wire cut through and is bridging out. This is subsequently powering the park light circuit when you power up the brake circuit.
I am only guessing about the body control module, it could be the wrong module for the programmed key or the wrong BCM for the car entirely. Calais should have had a high BCm. This is printed on the tag. Check this out & see how you get on. This could be why you can't turn your lights on from the switch as the calais BCM has the light timer function.
I have had this problem before on my VS , with the head lights and dash lights coming on when braking. It was caused by one of the brake light globes being turned too far in the socket and short circuiting the Brake and tail light circuits. Try removing the brake light globes and see if the problem stops. Then put the globes back in one at a time and test the brake lights after each one. This should fix it , or at least identify which side has the problem.