New V3 KE Hot End: Code 2509 : Temp reading -90 C at room temp

Good day!

I just replaced the hot end on my Ender 3 v3 KE.
After the replacement the unit fails the startup self test with error code 2509, which isn’t surprising as it is registering in the negative 90’s C at room temperature.

I double checked both wire pair connections and can’t seem to find what might be out of sorts.

Had anyone had any experiences that might help guide me in the right direction?

Thanks in advance!

Was it successfully repaired? do you know the cause?

It turns out that I had the wiring pairs reversed. When I removed the original hot end, the “saddle” that oriented the one set of wires fell off. Unplugging both sets of wires and then carefully watching the orientation in a number of YouTube videos got things back on track.