E-OBD

The OBD-II standards have now been adopted by the European community and developed for the European automotive sector for compulsory implementation in 2000MY.

E-OBD

The European Parliament has issued its own directive aimed at reducing pollution from motor vehicles which is commonly known as ’EURO-3’, and is a development of the earlier EU-1 and EU- 2 regulations.

In addition to lower emission limits, the directive also covers the monitoring of emission-related components and functions during operation, based on the US OBD-II model.

If an emissions related fault is diagnosed by the engine management system, which results in a significant increase in the vehicle emissions, a Malfunction Indicator Lamp (MIL) must be illuminated to inform the driver that the vehicle needs to be checked for emission-related faults.

For petrol-engined passenger cars up to a total weight of 2500 kg the following maximum pollutant limits have been set by the EURO-3 legislation:

• Carbon Monoxide (CO) – 3.2 g/km
• Hydrocarbons (HC) – 0.4 g/km
• Nitrous Oxides (NO_x) – 0.6 g/km

E-OBD stipulates the monitoring of the functions of the following systems:

• Catalytic converter
• Catalytic-converter heater (where applicable)
• Misfire detection
• Fuel system
• HO₂ sensors
• Secondary-air system (if applicable)
• Fuel filler cap captive or monitored (where applicable)

The engine management system (ECM) monitors the above systems by checking the data from different sensors fitted to the vehicle and the associated data records stored in internal memory (memory mapping) to monitor environmental conditions and engine operation.

Default values for some components are stored in system memory, which the ECM uses if it cannot determine the environmental or engine operating conditions due to a faulty signal. If a faulty sensor is detected, the MIL warning lamp is illuminated when the fault has been confirmed over the relevant number of drive cycles.