A large number of fault codes appear after the annual inspection of automobiles, which may be due to the test method, which leads to the misjudgment of the vehicle system, rather than the fact that the car is really broken.
It's like: when going to physical education class, 1000m "DuDu" ran down like this, and ran to "Ah" with a stomachache and discomfort, walking for a while, drinking water, standing for a while, lying down for a while, and taking a rest. It may be so.
The annual inspection and test method can be judged as abnormal working conditions.
Fault codes may appear due to the test method.
The annual inspection of vehicles actually includes vehicle safety technical inspection and environmental protection inspection.
Safety technical inspection is to check hardware, such as appearance inspection, lamps inspection, etc. It is equivalent to taking a look when the car is parked, and it is unlikely to produce any fault codes; Environmental inspection is the chief culprit of the fault code.
Refer to GB 18285-20 18 "Emission Limits and Measurement Methods of Pollutants from Gasoline Vehicles (Double Idle Speed Method and Simple Working Condition Method)".
There are generally four methods for tail gas detection. What are they? Double idle speed method, steady state method, transient method and simple transient method.
Except for the double idle speed method, all other detection methods need to be carried out on the chassis dynamometer. Just put the two driving wheels in a place similar to a "roller" and run there.
Kind of like a treadmill. The other two wheels of the treadmill used in the car are in static contact with the ground.
In this case, by detecting the wheel speed of the system, such as what? ABS, ESP, passive tire pressure alarm, etc. , these fault codes may have come out.
Take an ABS as an example. He Xipeng said in the paper "Analysis of Active Wheel Speed Sensor in Automobile ABS System" published in the magazine "Automotive Practical Technology".
The working principle of ABS is to monitor the wheel speed through the wheel speed sensor at all times, and then calculate the slip rate through ECU.
"Hey," why does one of them turn so slowly? Finally, adjust the braking force of the wheel to prevent the wheel from locking.
During the annual inspection, when the driving wheel is turning and the other two wheels are not turning, ECU thinks there is something wrong with the car, and emergency, emergency and fault codes all jump out.
Some staff members have deviations in testing and vehicle use methods.
In addition to the test conditions, some staff members are not skilled in business, which may also cause the car to give it a fault code.
For example, if the four-wheel drive is checked as two-wheel drive, not only will there be a fault code, but if it is not done well, the car will really break down.
Yan Jin and others published a paper in the magazine Automation and Instrumentation to share with you. It can be said that the research of braking force detection system for full-time four-wheel drive vehicles.
Roller reaction brake detection platform is widely used in most domestic motor vehicle security inspection institutions. When the other two wheels of the four-wheel drive touch the ground, it may cause damage to the gearbox, differential and other components.
Tell people the truth: the "roller" can only measure two wheels. When the four-wheel drive is put in the past, all four wheels will move, and the other two wheels will not work, and the car will break down.
You've been holding your breath. Will it hurt internally if you hold it for a long time?
Someone else's car, the test does have rough problems.
Some people say that violent car inspection leads to trouble codes in the car, which does exist.
For example, it can be found online. Jack bauer hotline reported a news from June, 5438 to February, 2020: During the annual inspection of a BMW 3 Series engine, the engine exploded due to the sound of inspectors stepping on the accelerator there.
In this case, the inspector felt that the car was not his own anyway. "ouch!" I'm so busy today. Do it one by one, by hook or by crook. "Ouch" really hurts, but don't worry too much, after all, it is also a minority.
Some will eliminate themselves and only remind them of abnormal working conditions.
If there is a fault code after the annual inspection, don't worry, as just explained, in many cases, it is really a false alarm.
As long as the car is restarted or driven for a certain distance, the fault code will be eliminated with high probability.
For example, passive tire pressure alarm is to judge whether there is a problem according to the "wheel speed difference".
It reported an error during the test. After driving for a while, it was found that there was no wheel speed difference, and some of them were automatically calibrated. Some pressed it once, tested it again, and it was ok.
Some fault codes may really be broken, so be careful.
However, if there is a fault code unrelated to wheel speed monitoring, or no matter how many times the car is restarted and how long it has been driving, the fault code will still exist, for example, after 3 days.
Then it is possible that the car is really damaged by them, and it is necessary to go to the auto repair shop for inspection.
So, you see, you have to pay the inspection fee. When you pay, you have to keep the invoices and documents yourself.
There is a fault code in the annual inspection, which is generally a false alarm.
Therefore, generally speaking, the fault codes in the annual inspection are mostly obtained through the "drum" inspection during exhaust gas detection, which is generally related to the wheel speed problem and is often a false alarm.
In rare cases, it's really bad. As soon as you step on the accelerator, the smoke rises, or is it obviously the steering wheel? Skip the transmission fault code, which requires special attention.
For example, the engine fault light pops up during inspection, and the gearbox fault light pops up ... these are all important issues.
After the annual inspection of the car, the fault light came on. Is it broken?
If I really check the car like this, I'm one in a million. It's really broken. What should I do? How to claim compensation from him?
What preparations can be made before the annual inspection to pass the annual inspection more conveniently and safely?
A friend asked the scalper for an annual inspection. 200 yuan, too much trouble. What's the difference between taking it yourself and taking it from a scalper?
We took a video and watched it, and found that it might be more convenient for us to do it than the scalper. The time of bargaining in the middle is saved, which is cheap and fast. So can girls. Just follow the video.
Keywords: annual inspection
Watching videos is also very simple. Just pay attention to "spare tire says car" and reply to the keyword "annual inspection".
Give you a practical small dry car every day, with words, audio and video. Pick any version you like, and "Spare Tire Says Car" is waiting for you to play.
refer to
[ 1]GB 18285-20 18。 Emission limits and measurement methods of pollutants from gasoline vehicles (double idle speed method and simple working condition method) [S].
[2] He Xipeng. Analysis of active wheel speed sensor in automobile ABS system [J]. Automotive Practical Technology, 20 16.
Yan Jin, Ye, Shao, Zhang Xin. Research on braking force detection system of full-time four-wheel drive vehicle [J]. Automation and instrumentation, 20 16.
[4] Who will pay the 50,000 maintenance fee for the cylinder explosion of BMW engine during the annual inspection?