This fault code appears in automobile maintenance. Is it serious? How to treat it?

Isn't this a serious mistake? When these fault codes appear, your engine should not work properly, right?

Your vehicle engine should be an electronically controlled diesel engine. The throttle control design of electronically controlled diesel engine has two potentiometers. A potentiometer has three wires, one is a 5-volt power supply wire, the other is a change signal wire and the other is a ground wire. The signal voltage induced by the two throttle valves is a double voltage and double proportional relationship, and the power supply voltage is 5 volts. When a line or component fails, if the signal voltage is not in double proportional relationship, the above fault code will be generated. At the same time, the engine speed limit is always 1000 rpm, and the throttle engine speed remains unchanged.

Analyze your fault code in detail. Without analysis, 28A9 and 28A4 will naturally be normal after processing, that is, the first fault code is generated by the fault reflected by the last two fault codes, and 28A4 is short-circuited to the positive pole, indicating that the signal line and power line of the throttle signal potentiometer 1 are short-circuited. 28A9 should be a short circuit between the signal wire of throttle potentiometer 2 and the ground wire. As for the cause of 276F, I think it should be like this. In the engine ECU, multiple power outputs are used to provide power for each sensor. Some sensors are powered by a 5 volt power supply, and some two or two sensors * * use a single power supply. * * * In the sensor with power supply, if the power supply of a sensor has a short circuit fault, it will inevitably affect the sensor with power supply. In this way, the decoder will also report the fault code of the sensor with power supply, although the sensor may not be faulty. So as long as 28A4 and 28A9 are handled, the other two fault codes will disappear automatically.

The specific repair should be to unplug the throttle sensor and measure the voltage between power supply and ground. If it's all 5 volts, make sure it's the accelerator pedal. Just replace the throttle sensor. If it is not 5 volts or the signal line is also 5 volts, then the line should be checked. In my analysis, it is rare for multiple lines to be short-circuited at the same time, which should be the cause of the accelerator pedal.