Fault code 69!

[Jonny_b]

I've been trying a spare ecu on my car today and the engine cutout when I was on the motorway - revs slowly died and it felt like a fueling issue.

Once stationary it immediately restarted and has been fine all day.

Plugged in my EcuMate in and fault code '69 neutral switch input fault' came up - has anyone had any experience this?

Thanks