Radiator

Radiator health in Service Mode: where the percentage comes from and why it falls

Firmware from the 2026.20.* branch added a radiator health percentage to Service Mode. In the summer of 2026 it sagged across the fleet: 79% on a refreshed Model 3, 83%, 76%, and for one owner 100% turned into 65% in three weeks. The number comes back to 100 neither after cleaning the stack nor after fitting a new radiator. What sits behind it, and when it really is about dirt.