1. On your first point, do you mean that I would see this error if the temperature is above the temperature I have set? If so, why do I not see the same error on the other display for the bottom half of the cooler?
2. Possibly. How do I determine if the PCB is faulty beyond the troubleshooting I have done?
They are both mounted on the right inside the unit, one for the top cooling area and another for the bottom. Here is link to the sensor on their site: http://www.4caple.co.uk/sensor/product.pl?pid=1354255&query=wi6123.
I'm pretty sure that the sensors are both OK, because if I switch them over, the problem doesn't move from the top to the bottom, I still have the error code for the top. The same applies if I switch over the sensors connections on the PCB, the error code continues to relate to the top chamber.
Here's a link to the PCB: http://www.4caple.co.uk/pcb-board/product.pl?pid=1954798&query=wi6123.
I don't really want to purchase a new PCB unless i can verify that it is indeed the PCB at fault (assuming its not the sensor, and somehow my troubleshooting method is flawed).
They may well be temperature sensors rather than defrost sensors. I referred to them as such, as they were referred to as such in other posts on the internet that I found on this site. There is very little useful information in the user manual or on the internet on Caple units from what I could find.
I think I'm just going to order a replacement PCB, as i can't see what else could be the cause given the troubleshooting. Thanks for your help.