Diagnosis b4 repair

[tonigau]

I'm not a refrigeration tech, but want to identify most probable cause before taking to service to minimize their time (my$).

I have a 238L DC(12V/24V) fridge/freezer Beier BR238C4 that has developed a cooling problem - doesn't get cold.
This fridge did get returned to me once before with a not getting cold fault but it was working ok on test for a few days. Everything appeared normal.
It was suspected the solar system was insufficient (it was problematic due to a pressure water pump operating too often) or possible the bumpy ride of 200+ km's had a therapeutic effect on the fridge. it ran for another six months after.

I have checked for leaks with soap water on all accessible joints on the pressure side, both running & off. cant access the joints to evaporator yet as this needs surgery to the outer steel skin.(last resort)

The fridge has a 70w Domus DC compressor 3 phase BLDC, very simple refrigeration circuit, fan cooled condenser, capillary tube metering, on/off mechanical thermostat.

Any way here is a description of symptoms.
Evaporator not cold, compressor discharge pipe just warm, compressor suction tube just cool, capillary tube COLD, top section of check valve cold.
Compressor starts of with normal current of 6A, then slowly over about 100 seconds to 2.2A, RPM is constant.
For normal operation current will drop to 4.5 ~ 5A before thermostat cuts out.

Q. If there were a blockage/fault in the check valve would compressor current(work) be high. I would suspect so. ?

Q Because the compressor current is dropping well below normal would this be indicative of low gas charge(leaked) ?

Attached is a test done last year on same model (different unit) shows normal compressor current.