A 2013 popular limo with a distance of approximately 160,000 km and a direct turbo boost engine with 1. 8 tsi cylinders and a 7-speed wet double-disconnected automatic transformer. The vehicle entered the plant for repairs owing to a failure of the engine that was twitched and accompanied by an epc light。
(c) disorder diagnosis: test tests after taking over the vehicle to verify the failure, connect the ignition switch to try to activate the engine, start the engine successfully but with a clear glitch, while the epc and engine failure lights on the dashboard are frequently lit. In situ, engine acceleration is largely normal。
The connection malfunction detector (vas6150b) enters the engine control unit (j623), reads the fault code and reads the code "p0303" meaning "cylinder 3 detects no fire (static). Based on the tips of the failure code, a preliminary determination may be that the 3rd tank lacks fire, resulting in an imbalance in engine power output and causing the engine to blink。
The maintenance staff used vas6150b to enter the engine control unit's bow }conductive measurements interface to view the actual value of the one-to-four-cylinder fire-deficit counter (table 1) and found that the actual value of the three-cylinder fire-deficit counters was 229 times and was still increasing. The engine control unit monitors engine velocity fluctuations through a curved position sensor and judges the empty cylinder in conjunction with the signal of the cam axis position sensor. When the cumulative fire deficiency in a tank reaches the reference value set in j623, j623 will store the failure code for the tank and light the engine failure light on the dashboard. For some models, when the number of fires in a tank reaches the system reference value, the tank is also cut off from the spray to ensure environmentally sound emission control requirements。
After identifying the approximate range of malfunctions, the maintenance staff diagnosed themselves through the vas6150b execution element, selected the “616 cylinder 3 jet valve” and activated it (figure 1). The sound of the “things” of the oil jet operation was not heard near the engine room, but data changed on the start time of the jet control on the vas6150b diagnostic interface, which judged the failure of the three cylinder jets and their associated circuits based on test results。
The maintenance staff connected to the specialized detection equipment (vas 1598/39) and re-entered the fail detector's oscillator interface, measuring the wave shape of the four ends (ends 32 and 34 for conductor 60, and end 5 and end 6 for conductor t8y), respectively, on the j623-controlled 3-cylinder line in the event of engine failure, as shown in figure 2. Combined with the analysis in figure 3, it is known that the control signal sent by j623 to the 3-cylinderjet was sent by the end of the conductor t60, the end of the conductor t8y, the end of the conductor t8, which was entered into the 3-cylinder (n32), and the end of the n32, the end of the conductor t8y, which was ultimately entered through the end of the conductor t60 to j623, forming the control circuit。
Based on the abnormal wave-form tips in figure 2, the maintenance staff focused on checking the line between the conductor t8y end 6 and the conductor t60 end 34, which revealed anomalies in the line through the front left beam, stripping off the beams and finding adhesives from burning inside the beam, where the line broke between the conductor t8y end 6 and the conductor t60 end 34. In addition, maintenance personnel found evidence of welding repairs in the front left beam and the radiator frame, suspected of having been improperly operated during the previous accident repair, causing damage to the beams, which were typical of human faults。
Fault removal: handle and test the attached threads, start the engine, slow and slow, and troubleshoot。
Relevant information:
Elsa 6. 0
Maintenance manual for magotan, 2014 (including circuit maps)
