i just had an mot done and failed on a few things. (if anyones interested i can put that in another thread.) one was the driver side rear brake light out. went to halfords and bought a set. though if im changing one i might as well change the other. once i had changed them though it was still out. the side light works but not the brake light??? it is in the right way (only way it fits) any ideas what could be causing this? need to find the fault asap to re-test. could pay the garage to do it but would rather keep the cost low if i can. thanks for any qiuick responses.