How do you fix a TV screen that has gone red?

You have to open the back of the tv(remember safety),look for three knobs,a red,a blue,and a green knob.You will have to tune each knob seperately,tune down the red and adjust the other two until your image is repaired.This could be caused by exposing your tv to a magnet.Remember that this is dangerous and you can shock.(",)

I would highly advise against tuning anything on a TV which has changed display on its own. I use to repair electronics for living and a symptom like that indicates a circuit failure in the TV. Any 'knobs' better known as variable resistors are pre-set at the factory and usually painted on one side to indicate and keep the factory setting. The only time you should mess around with those is if you do a CRT (aka tube) replacement to recalibrate the electronics for the new tube display.

To fix the described condition you will have to troubleshoot and replace the failed component (usually a transistor or an IC [integrated circuit]). You can try doing this on your own but a repair shop is usually the better choice since they have access to schematics, troubleshooting equipment and replacement parts. Good luck!