Mod CNES 3866. Got a call to say that F4 was coming up on display of this fridge.Customer called Liebherr who said it was evaporator sensor. Wondered if anyone could confirm this as she wants quote to do job as liebherr want £100 + parts to come out.
Check fan is operating correctly this F4 fault can be caused by fan stopped due to ice build up, the sensors are prone to water ingress which gives a faulty reading, i’ve used a hairdryer to dry them off & put a smear of silicone sealant on & it cured it for me .