Patent ID: 9677452
Date: 2017-06-13
CPC Classifications: F01N,F02M,Y02A,Y02T

Claim:
1. An abnormality diagnosis device for an exhaust gas control apparatus, the exhaust gas control apparatus being placed in an exhaust passage of an internal combustion engine and the exhaust gas control apparatus including a selective catalytic reduction catalyst, the internal combustion engine including: a supply device configured to supply an additive to the exhaust gas control apparatus, the additive being ammonia or a precursor of the ammonia; and an EGR device configured to allow some of exhaust gas to flow back from the exhaust passage to an intake passage, the exhaust passage being further downstream than a position of the supply of the additive by the supply device, the abnormality diagnosis device comprising an electronic control unit configured to: i) acquire a NO ii) diagnose an abnormality of the exhaust gas control apparatus by using the acquired NO iii) prohibit the abnormality diagnosis regarding the exhaust gas control apparatus in a case where some of the exhaust gas is allowed to flow back by the EGR device and the amount of the additive flowing back along with the exhaust gas exceeds an upper limit value.