Patent ID: 8631645

Claim:
A thermal management system comprising: a first electronic circuit configured to determine whether a catalytic converter is active; a second electronic circuit configured to determine whether a SCR catalyst is active; and a third electronic circuit configured to adjust an air and fuel ratio of an engine to operate at a stoichiometric ratio and retard spark of the engine when the catalytic converter is not active, wherein the third electronic circuit does not perform post fuel injection while the catalytic converter and the SCR catalyst are not active, wherein the third electronic circuit is configured to at least one of determine a first active volume of the catalytic converter and whether the catalytic converter is active based on the first active volume of the catalytic converter, and determine a second active volume of the SCR catalyst and whether the catalytic converter is active based on the second active volume of the SCR catalyst, wherein the third electronic circuit is configured to perform the post fuel injection in response to the catalytic converter being active and the SCR catalyst not being active, determine a weighted average based on a plurality of temperatures, determine the second active volume of the SCR catalyst based on the weighted average, and perform the post fuel injection in response to the second active volume of the SCR catalyst.