Patent ID: 11879367
Assignee: PACCAR INC
Field: Environmental technology (Chemistry)
Classification: CPC F  Y | IPC F

Claim 4:
5. The method of claim 1, further comprising:
while operating the diesel engine, operating the exhaust after-treatment system to eliminate ammonia present in the close-coupled selective catalytic reduction system;
after operating the exhaust after-treatment system to eliminate ammonia present in the close-coupled selective catalytic reduction system, controlling the diesel engine such that the exhaust gas flow has a variable level of NOx gases as it enters the exhaust after-treatment system;
measuring NOx gases with the first NOx sensor and the second NOx sensor as the level of NOx gases in the exhaust gas flow as it enters the exhaust after-treatment system varies; and
using the measurements taken as the level of NOx gases in the exhaust gas flow as it enters the exhaust after-treatment system varies to determine a level of error in measurements provided by the second NOx sensor.