Rear fans not working on 1200 will result in fridge temps 'chasing' ambient air temps....as they rise during daytime so will fridge temps and then as ambient air temps go down in evening so will fridge temps
Could be as simple as the t-stat for fans is bad or loss of 12V to fans (bad in-line fuse)
T-stat should start fans at 130*F and stop them at 115*F (Condenser Fin Temps)
Then there is the 'frost management' cycle that shuts down cooling every 49 hrs to minimize frost on fins in food compartment.