Symptom: 06 years Brilliance BMW E90325i car sometimes the engine starts difficult, and sometimes it can be a smooth start, and start the dashboard after the airbag warning light is not extinguished. The car is out of the accident, but the damage is not serious, and the engine is difficult to start the case sometimes no failure occurs when feeling like a starter turning weak.
    Troubleshooting: because the car into the plant can be successfully started, so the maintenance staff to check the appearance of the engine harness and the lights on the instrument and other basic conditions, but did not find a clear problem, but the airbag warning light is not extinguished.
    For the car to start this difficult and sometimes the failure, often maintenance personnel check the phenomenon does not appear when the inspection, so maintenance personnel more difficult to determine the real cause of failure. Users reflect the car has been in other repair shop has replaced the battery and generator, but did not rule out the failure, then the user asked to replace the starter test. However, maintenance personnel believe that if you do not find the cause of the malfunction, you should not blindly replace the accessories, even if the replacement of the starter is difficult to determine whether the exclusion of the fault. And according to the maintenance staff on the BMW car repair experience, BMW Brilliance 325i sedan starter rarely had problems, it touches on this car generators more prone to problems, but this car has been replaced by the generator, and the original Factory accessories, so should be no problem.
    Connecting the original BMW fault diagnosis device GT1 for the whole car scan, in many systems are stored in the fault code. The fault code for the generator is stored in the engine control unit, but the service personnel suspects that the fault code is caused by pulling the motor plug at other repair shops. Clear the stored fault code, after the test did not appear again. Because the dashboard on the airbag warning light is always lit, so use the diagnostic instrument into the airbag system and found that there are multiple fault code, clear the trouble code and then start the engine again, and then read the airbag system fault code again, There are only two fault codes on the rear harness tensioner.
    After checking the rear seat belt, it was found that the seat belt mounted on the seat was shorter than the normal section of the seat belt, indicating that the seat belt of the rear seat had been detonated. In this need to remind the maintenance staff to note that the BMW seat belt is not already detonated, you can observe the seat belt buckle has been shortened on it, but other cars may not be the same. For example, the explosion-proof device of the explosion-type seat belt of a Mercedes-Benz is generally mounted on the seat belt fastening device and is not mounted on the buckle seat of the seat belt. Moreover, the BMW Department of the airbag can generally be used three times, the collision stored in the fault code can be used to eliminate the fault diagnosis device GT1.
    Replace the seat belt buckle seat, enter the airbag system to clear the fault code, the dashboard on the airbag warning light can be extinguished normally. Then check the engine difficult to start the problem, but difficult to start the fault has not appeared, if so let the vehicle factory, the user will certainly come back. Recalling the entire maintenance process, maintenance staff suddenly had a question, why the maintenance of the car before the repair shop only replaced the front of the airbags and seat belt buckle seat, but did not replace the back seat belt buckle it? And the fault code is not cleared? The most likely reason is that the repair shop does not have a dedicated instrument to detect the car, and they may not see the fault code at all, but rather that the airbag and the front seat belt buckle seat replacement airbag warning light Will go out. But the replacement of these parts after the airbag warning lights are not extinguished, they have no way.