Data flow is an important basis for us to determine the fault, but in the maintenance process, many maintenance masters can not effectively analyze the data flow, resulting in inaccurate determination of the fault point. This issue of small rail brings you a “weird” data stream. Through the analysis of this data stream, we can know why the engine is limited to torque lack of power?
From the conversion of the heat energy of fuel combustion into the kinetic energy of crankshaft to the rotation of wheels to provide kinetic energy for the whole vehicle, there are many links in the process, which is the result of the joint action of multiple systems. As long as one of the systems is abnormal, it may lead to the lack of power of the whole vehicle. The reasons for the lack of power are as follows:
It can be seen from the above figure that there are many reasons for lack of power, so how should we judge the real reason of lack of power?
Most of us will first look at the fault code when troubleshooting the lack of power, or rely on our experience to see whether the corresponding data flow is normal, but there is no intuitive judgment on whether the engine is really limited. Now the small rail will teach you a data flow. Through this data flow, we can determine whether the engine is limited, why it is limited, and how to check it lack of power?
In this data stream, we can see that the value of the data stream is 12296, which means that the torque limit is activated. Only when the torque limit is 0, it means that the engine torque limit is not activated. When we want to see why the engine torque is activated, we must convert the torque limit value into hexadecimal as follows lack of power:
Note: for decimal to hexadecimal conversion, you can use Baidu online conversion. After conversion, it is less than 16 bits and needs to be filled in the front.
The following figure shows the corresponding value of the data flow of “torque limit” in the calibration tool; It is also sixteen bits in the calibration tool, which is one-to-one corresponding to the number of bits we convert lack of power.
Note: the above figure is hexadecimal, in which a represents 10, B represents 11, C represents 12,…, f represents 15, and 16 positions from 0 to f correspond to the 16 positions converted in the data stream one by one.
This data stream contains 16 bits, and each bit represents a torque limiting module.
Note: each bit is activated, that is, the bit is set to 1 lack of power
All these modules will calculate a torque value. These torque values are compared with the current minimum internal torque value. If it is smaller than the current minimum internal torque, the module is set to 1.
1. Bit0 — torque limit caused by faulty module