An exhaust system is disclosed. The exhaust system has a first sensor disposed to sense a first temperature of an exhaust flow and a second sensor disposed to sense a second temperature of the exhaust flow. The exhaust system also has a controller in communication to receive from the first and second sensors signals indicative of the first and second temperatures. The controller is configured to compare the signals indicative of the first and second temperatures during exhaust system thermal equilibrium, to determine whether at least one of the signals indicative of the first and second temperatures is inaccurate based on the comparison, and to affect a system reaction if it is determined that at least one of the signals indicative of the first and second temperatures is inaccurate.