Vehicle failure: the instrument reports that the airbag light is faulty.
According to the owner's description: half a month ago, the airbag light flashed occasionally, and sometimes it went out automatically inadvertently. Until now, the instrument airbag light has been on.
Check steps:
Brother started the vehicle at an idle speed of 800 rpm, and the airbag light was always on. Under normal circumstances, the fault light will go out automatically after starting for two or three seconds.
The faults read by the computer are B0026, B 1327 and B0882. The key point is that the first fault shows that the main driver airbag circuit is open, and Pongo initially judges that the circuit is open.
The computer was used to clear the fault, but the fault code B0026 could not be cleared after trying. I told you before about the key detection lines (commonly known as hard faults) that cannot be cleared. The airbag computer can read and clear it, indicating that the problem is not the computer.
To check the wiring, first remove the airbag and steering wheel, and then remove the fixing screws on both sides of the steering wheel. There is a bulge in the middle of these screws, which can only be removed with professional tools.
Pull off the yellow plug and remove the airbag.
Check the airbag plug for signs of oxidation and poor contact.
Next, use a multimeter to measure whether the air bag hairspring is conductive. Before measuring, the plug connected to the computer under the hairspring must be unplugged, otherwise the consequences will be very serious.
Airbags can be triggered by a voltage of about 2 volts. Strictly speaking, it can't be measured by multimeter, otherwise it will cause other airbags to bounce off.
There is a two-wire plug above and below the hairspring.
After unplugging the plug, you can use a multimeter to measure whether the hairspring is conductive, open or short-circuited. Check whether there are white lines at different times.
In order to further verify the quality of the hairspring, Pongo found a resistance of 2.7 ohms, which is approximately equal to the resistance of the airbag.
The resistor is connected in series to the plug of the computer under the hairspring, which is mainly used to cheat the computer. If the fault light can go out, it means that the problem lies in the hairspring, the hairspring plug or the airbag itself.
After the vehicle is started, try that the airbag light is turned off.
Next, connect the hairspring computer plug and string the resistor on the hairspring. After the vehicle started, the airbag light of the tester came on, and Pongo concluded that the hairspring had been damaged, which led to the broken wire.
For further confirmation, Brother Pang turned the hairspring many times by hand, and I found that the airbag light suddenly went out once. Combined with the above tests, Pangge has 100% confirmed that it is a hairspring fault.
What is an airbag hairspring?
The airbag hairspring is actually a wire harness. Because the main airbag rotates with the steering wheel (it is conceivable that the steering shaft of the steering wheel is wound with a certain length of wire harness, which can be loosened or wound more tightly in time when the steering wheel rotates, but it is also limited, so it is necessary to ensure that the wire harness will not break when the steering wheel is hit to the left or right), so there should be a margin for connecting the wire harness, and it is necessary to ensure that the steering wheel will not break when it turns to the limit position. Therefore, the emergence of hairspring can solve this problem well.
Fat brother concluded: Fat brother suggested that you don't have to think too much about the damage of the hairspring, just replace it with a new one, and the maintenance is of little significance. Even if it can be repaired, it will be useful. Although there is something wrong with the airbag, it does not affect the driving of the vehicle. Please solve the problem as soon as possible. Think about what you spent so much money for. It's better to have airbags than nothing.
Welcome to inquire about vehicle maintenance and used cars. Friends you like can pay attention to it. There will be more car knowledge to share with you later.
In the next issue, Brother Pang will share with you the recently collected used cars within 10,000 yuan, including cars, bread and joint venture mini-cars on rotten streets.
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