Hi so I scanned my 04 G35 Coupe A/T bringing a P1705 'throttle position sensor' and U1000 in my transmission along with C1136 in the Ecm for 'engine signal 6' obviously its not communicating right but I dont know how to diagnose this, would this be a fault in the Valve body itself internally or a wiring issue? The car doesn't show any signs of limp mode or issues when driving. I also can't use cruise control.

 

C1136 is ABS related so no cruise. Most likely ABS sensor, you'd need a deeper scan on the module or get a DVOM and check the resistance in the wheel speed sensor(s). The one with odd reading will be the bad guy.
P1705 is for TPS which i assume it's inside the T-body. I have 2 t-bodies on my HR with internal TPSs. TPS does wear out so a t-body swap should fix it.
U1000 is a general code, i got that also and it doesn't affect my car in any way.

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