Hi Steve,
Did you get to the bottom of this? I have a Modus that I have had to let the customer have back with virtually the same problem except the switching is going the opposite way, ie, intermittently dropping to 0v. I have got to get the vehicle back in as soon as I get time when I will check back to the ECU but the fault seems to get worse as the temp increases so I don't think the fault is going to be in the loom.
I have attached 2 images but what I am not sure about is the slight movement in the one with 0v that looks as if the ECU is "trying" to switch IYSWIM.



Regards,
Bryan.