messiah and gran turismo 4

[jfbt]

how kan i turn off messiah chip (it's about 3 years old)so i can play gt 4 original

[Hansi]

If it is Messiah 1, I dont think you can.
But you can try the "PS1/DVD" mode.

If not in standby mode, go to standby mode by pressing reset 2 seconds.
Press reset quick to start the PS2. Then quickly press reset 2 times more.

If you have Messiah 2, go to standby mode and then start by pressing reset and keep it pressed until the blue light is turned on + 5 extra seconds.