Case IH Farmall 100C Repeated DEF Faults and Limp Mode. What to Diagnose Before Replacing Parts
Some Case IH Farmall 100C owners run into a cluster of DEF issues on the same tractor: coolant showing up in the DEF tank, “DEF poor quality” derates, a “DEF frozen” alert popping up in warm weather, injection failure messages, and limp mode kicking in again and again. It’s a rough experience, and understandably it…