code p0720

i have a code p0720, output speed sensor code, i changed the sensor and still throws a the code, could it be the input speed sensor problem, let me know what you think thanks

oh yeah i failed to mention that its a 4l30 transmission, when i unplug the input sensor it still shifts the same.... long 1-2 the rest are fine and it doesn't throw a code.... when its pugged in it shifts the same then throws the code, if i unplug the output speed sensor it obviously doesn't upshift at all..... i hope this helps a little better, thanks