Car diagnostic tool - Xhorse Key programmer
1、Models: New Sunny
2, mileage: 32480
3, the phenomenon of failure: the vehicle in the idle condor xc-009 state or at low speed, sometimes there is no response to fuel, and then turn off, after the flameout can be smoothly started, and returned to normal.
4, fault code: Enter 01 engine control unit to read the fault code, the system is normal, without any fault code.
Maintenance station inspection and diagnosis:
1. The road test failed to test the fault phenomenon described by the customer, but the customer told us that it was accidental, sometimes not, and that the vehicle exceeded the warranty quickly, hoping to give a one-off solution to the problem.
2, enter the 01 engine control unit to read the fault code, the system is normal, without any fault code.
3, When the vehicle is idle at idle speed autel md808 or at a low speed, consider the oil circuit, the power supply system, and the line problem. The control unit is unreliable and the sensor is damaged.
4, The engine fuel pressure is tested. At idle, the pressure of the low-pressure fuel is 6.7 bar, and the pressure value is normal. Considering that the gasoline is not fully burned, the flame may be extinguished or it may not be accelerated. Carry out fuel tank cleaning on the fuel system. Replace the steam filter and clean the carbon deposit in the combustion chamber. The nozzle is also cleaned. The fault persists.
5, The next step is to check the engine's power control system, power supply relay circuit, power supply relay itself, engine control unit circuit, and ground. One week after leaving the station again.
6, connect the remote diagnostic instrument, carry out the road test, carry on the data measurement of each sensor and analyze the trouble of the vehicle.
From the above data, the engine's intake air amount and ignition advance angle are all within the normal range, as well as the fuel rail
Adjustment of system pressure did not find any abnormal data.
For the above test data cgdi key programmer remote diagnostic instrument for data measurement and data download corresponding observations, at the same time with the road test status simulation failure. From the data, the pressure of the reaction engine and the voltage of the throttle position sensor are normal. However, when data monitoring was downloaded, it was found that there was no working signal at throttle position 2, and the fault point was locked.
From the above data, it can be analyzed that the throttle control unit is damaged and there is a short-circuit fault in the line from the throttle valve to the engine control unit. Measurements are made on the connection line of the throttle valve to the engine control unit. To find pin virtual connection or short circuit, the fault point is attributed to the throttle control unit. Replaced the new throttle control unit, tracked back to the one-month failure did not appear, troubleshooting.
Summarize and share:
In the face of some trouble-free storage of fault cars, it is necessary to fully consider, the reason why the number of maintenance of the car so much, mainly technicians are starting from the oil road to repair. Blind replacement accessories. In addition to experience, Hyundai Motors has to use the latest diagnostic equipment to repair faulty vehicles, which can greatly reduce maintenance time and improve maintenance efficiency. Reduce customer complaints.
