This paper studies up on the strategy for failure diagnosis of wall-flow DPF system based on pressure drop characteristics.

DPF failure diagnosis is carried out by on-board smoke hanging test, to verify the feasibility of this diagnosis strategy, no-load, medium load and full-load test are respectively carried out.

And DPF technology is the mainstream technology of tail gas after-treatment technology for light vehicle, the failure diagnosis of DPF is the key point of OBD system in the entire DPF technology.