Exam 19: On Board Diagnostics

Consider a 2018 OBD-II-compliant and Tier 3-compliant diesel engine. What factor or threshold of excess emissions is typically required to illuminate the MIL when a fault in the diesel particulate filter (DPF) is detected?

Technician A says that only the fuel system monitor will set DTCs for a misfiring injector. Technician says that the fuel system monitor and misfire monitor will set multiple DTCs. Who is correct?

Technician A says that any DTC will immediately illuminate the MIL in the driver's view the moment one is detected. Technician B says that all OBD-II DTCs will take several trips to confirm that a fault is active before switching on the MIL. Who is correct?

Technician A says that the OBD system on a diesel is continuously judging all major emissions systems for faults. Technician B says that some emissions monitors do not run every drive cycle and take time to correctly judge emissions system operation. Who is correct?

Which of the following is NOT used by the OBDII (On Board Diagnostics Generation II) system to prevent emission systems from fraudulent testing and tampering?

Technical standards for OBD (on-board diagnostic) are developed by the

Which of the following is NOT included in the OBDII (On Board Diagnostic Generation II) systems for diesel engines?

Which OBD input sensor will detect less fresh airflow into the engine when the EGR valve opens because EGR gas replaces fresh intake air?

An enhanced OBD-II code will be indicated by which position in the SAE code structure?

From its inception, an essential function of the OBD (on-board diagnostic) system was its use as a tool for emissions inspection and maintenance programs, often called:

A diagnostic approach using OBD (on-board diagnostic) data is unlike a symptom-based diagnostic strategy-a problem is identified based on a:

If a coolant temperature sensor shorted to ground, which emissions system monitor would first detect the fault?

Which of the following changes will take place when a manufacturer updates a software calibration and a technician uploads or flashes the vehicle with the new calibration?

The misfire detection monitor was noncontinuous until:

Which OBD-II monitor tracks electrical circuits operating engine components that can fail and cause measurable emissions?

All of these are possible monitor criteria for cold-start emissions, EXCEPT:

Before returning a vehicle to the customer after repairing the cause of the MIL being illuminated, the technicians should ______________.

Technician A says that MPC (model predictive control) of engines and powertrains can change the algorithm that generates a virtual lookup table to accommodate faults. Technician B says that MPC (model predictive control) can compensate for component wear and deterioration by generating a new set of lookup tables. Who is right?

While two technicians are discussing what to do to prepare a vehicle to pass an OBD-II emissions system inspection with an noncontinuous monitor DTC that causes the MIL to illuminate, Technician A says that the problem would need to be repaired and that the monitors all need to successfully run to pass. Technician B says that just the code could be erased before sending the customer to the inspection. The fault could be fixed after the vehicle has passed the OBD-II inspection test. Who is correct?

MPC (model predictive control) can compensate for component wear and deterioration by generating a new set of: