DTC P1258: Engine Over-Temperature Condition: Description
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The Powertrain Control Module (PCM) used the Engine Coolant Temperature (ECT) sensor to monitor the engine for an over temperature condition. This condition occurs when the coolant temperature is above 270°F (132°C). When an over temperature condition is present, DTC P1258 will set. The PCM will disable 2 groups of 4 cylinders by turning OFF the fuel injectors. By switching between the 2 groups of cylinders, the PCM is able to reduce the temperature of the coolant.