Hi,
I am having some freezer/defrost issues. The freezer coils keep frosting over - then icing up.

I have already changed the single bulb heating element (that was burnt out) to the double bulb element. This worked for a few months but now it is frosting/icing up again.

I got into the motherboard on the back and used a AC current detector to check the 3 lines (comp, defro, and Line). All showed current except defrost.

I them used jumper wires to go from the (defro to line)... The jumper wire then showed AC current and the Defrost element turned on.

At this point - what do I need to replace?
- motherboard
- coil thermostat (defrost limiter thermostat)
- temperature sensor
--- or some other part that I am over looking

Also - the comp and fan are functioning

Thanks for the assistance

WVU