I re-wired/soldered John's PAS sensor up last week as originally it was wired to the speed sensor on the KT controller, it should work if not damaged.. I had to change the sm connector, I know the wiring is correct.
Make sure you have connected the PAS to the correct controller connection.
PAS is Red 5v , Black Gnd and colour is Sig Blue or Green.
KT controller is Brown 5V, Black Gnd and Yellow Sig.
Red to Brown, Black to Black and Colour to Yellow.
Some PAS are directional so see what happens when you pedal backwards John, also is the magnet disc facing the right way with the correct magnet poles facing the sensor, Gap between disc and sensor needs to be about 1-2mm.
What we don't know is, is the hall sensor ok ?
You should see 5v between Gnd & V+ Brown/Red.
1v between Gnd & Sig Yellow/colour and 4 -5v when pas light is actuated.
Let me know if you want me to come and visit you John probably easier then bringing bike down to me use the Conversation/PM Inbox for security.