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R34 GTT 1998, engine light code 14 speed sensor. Came out of no where. Randomly stiff and light power steering. Speedo works so if i've read correctly the speed sensor inputs cluster first and the cluster gives information to the ecu. Nissan consult on a laptop saw no speed sensor input from the ecu. Is the speed sensor bad or is there something else wrong.

Wiring diagram for the whole speed sensor to ecu?

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If speedo is working then speed sensor is working. +/- 1V sawtooth (AC) signal generated by the speed sensor is translated into 0-5v square wave PWM signal at the speedo head and transmitted on the Consult bus for all the CUs to read. if the ECU can't see it then the TCU and the HCU won't be able to see it either. Would suggest that either head has a fault or the wiring is broken in some way. Look at the wiring diagrams for ANY Skyline to see how that signal typically gets around, then chase its wiring around with a multimeter. If you want to look for the signal itself, you will need an oscilloscope of some description.

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speedo, traction control and hicas works, looking for a new cluster atm. When I get a new one and the ecu still doesnt see the input something else is at fault. I also checked for continuity in the wire that goes from the cluster to ecu and it was fine. Could it have gotten grounded some where and the ecu fried something in itself?

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