A new generation of in-vehicle diagnostic system, the evergreen tree of automotive components

Main features of obdii tracking device

1. It can detect the working conditions of emission-related components and prompt the driver to repair and maintain the emission-related systems.

The obdii tracking device system has two monitoring processes: continuous monitoring and discontinuous monitoring. Continuous monitoring includes checking the intermittent misfire of the engine, monitoring of the fuel system (fuel correction) and comprehensive component monitoring. Discontinuous monitoring includes catalytic converter monitoring, exhaust gas recirculation and fuel evaporation system monitoring, oxygen/air-fuel ratio sensor monitoring, oxygen sensor heater detection and secondary air injection system monitoring. Some obdii tracking device systems for vehicles produced after 2000 also need to monitor thermostats. Vehicles produced after 2002 need to monitor the working conditions of the positive crankcase ventilation (PCV) device system.

2. Adopt a unified fault code and meaning, and can use a unified protocol testing tool and a standardized 16-pin diagnostic socket (DLC) for testing.

3. Diversification of diagnostic information. In addition to obtaining fault codes, the obdii tracking device can also provide information such as sensor detection values, control status, control parameters, and actuator on/off.

Fault code and fault indicator of obdii tracking device

1. Classification of fault codes of obdii tracking device system

The obdii tracking device system divides fault codes into four types: A, B, C and D.

Type A fault code

For fault codes related to emissions, the computer diagnostic program can detect such faults in a continuous cycle and light up the fault indicator.

Class A fault codes are the most serious category. Such fault codes will be set if the engine does not ignite intermittently, and the mixture is too thick or too lean. A type fault code reminds the driver that there is a problem with the vehicle's emission system, which will cause damage to the catalytic converter.

Class B fault code

Class B fault codes are the second most serious type of emission problem. Before the MI (Malfunction Indicator Lamp) fault indicator lights up, this type of fault should occur at least once in two consecutive driving processes. If it occurs during one driving process, but does not occur during the next driving process, the code of the fault is not yet "mature" and the MIL light does not light up. When the conditions for the MIL lamp to light up are met, the stored historical fault codes, failure records, and a frozen frame field data are exactly the same as when the Class A fault code is triggered.

Type C and Type D fault codes

Class C and Class D fault codes are derived from fault tests that are not related to emissions. Type C fault codes will light up the MIL lamp (or other warning lights), but type D fault codes will not light up the MIL light. Type C fault code is also called C1 fault code, while Type D fault code can be called C0 fault code.

2. The meaning of the fault code of obdii tracking device

The hundreds of fault codes, such as P0xxx and P1xxx type codes, indicate that there is a problem with the specific system or its branch system. The ten digits and digits of the fault code indicate that a part of the system is faulty. The following is the code defined by SAE and the system it represents:

P0100-Fuel or intake system failure;

P0200-Fuel system (only refers to fuel injection system) failure;

P0300-Ignition system or engine does not ignite intermittently;

P0400-Emission control system failure;

P0500-Idle speed control, vehicle speed sensor failure;

P0600-computer output circuit (relay, solenoid valve, etc.) failure;

P0700- Transmission differential, gearbox failure.

For example, the fault code P0302 is explained as follows:

3. Features of obdii tracking device system failure indicator

Malfunction indicator (MIL) is usually marked as amber "check engine" or "service engine soon" light. If a sensor is intentionally disconnected, the MIL light will not necessarily light up, depending on the degree to which the sensor affects emissions (priority) and the number of driving cycles required for the obdii tracking device to self-diagnose.

The working characteristics of the obdii tracking device system failure indicator are as follows:

⑴ When the computer detects a circuit or system failure, it can light up the failure indicator.

⑵If the engine does not ignite intermittently, the catalytic converter will be damaged and the fault indicator will flash.

(3) No failure of any component or system related to emissions has been detected, or there is a problem with the failure indicator circuit, and the failure indicator does not light up.

4. Obdii tracking device fault code reading and clearing method

There are many ways to determine the fault code generated by the computer:

1. Most production plants have special diagnostic equipment for monitoring and testing their vehicles. The diagnostic test equipment is used to read and record the input and output signals of the computer. The detection tool is called the scanner method, which belongs to the instrument reading and diagnostic testing. The device is also commonly referred to as a decoder. As long as you know the operation method of the detection and diagnosis interface and the instrument, you can easily read the fault code, but it is required to be equipped with a detector for the vehicle diagnosis system.

2. Another way to read the fault code is to flash the code through the dashboard lights.

The older models mostly use the check engine notation. Now almost all models use the scanner method.