•  The exhaust gas temperature must be at least 500 °C {932 °F} for the soot particles to burn; the temperature is detected by the catalytic converter exhaust gas temperature sensor and transmitted to the PCM.

•   The exhaust temperature before the diesel particulate filter is used as an input variable for calculation by the PCM, taking into account the values of other relevant variables.

•  Depending on the calculated exhaust temperature, the PCM then decides whether the regeneration process can be initiated or not.