I've got a problem with the wiring 😭 shorting

[Astra Coupe 2003]

I've got a problem with the wiring for some reason I've got no break lights they stay on and only when the headlights are on and I have no Parker's but if I put the Parker's on and put my foot on the brake they come on but as soon as a take my foot off they turn off and now I've got a headlight one dinner then the other FML seriously

 

[James]

Most likely a ground fault, check for corrosion of wires or terminals that connect to the chassis or body panels, particularly around the back of the car to start with.