Logo illumination on KDL-52XBR4?

Ok, so I bought a Sony Bravia 52' XBR4 model. Some of these TV's have defective screens and I happened to be one of the owners of a defective screen. I call up Sony and they come to my house and fix the TV. But, I was so busy that when they fixed it I didn't check the TV until after he left. Turns out the Logo doesn't illuminate anymore. I may be the only one who likes the logo illuminated but I don't know how to get it back on. I tried turning it on and off in the XMB, nothing happend. Help me please!!