The mileage is about 195 thousand km, with 2006 TOYOTA Camry cars equipped with 2.4L engine and AT transmission. Customer response: when the vehicle is running, the engine sometimes suddenly stalls itself. It has been repaired many times and can still be solved. Fault diagnosis: technician pick up the car, after many tests, fault reproduction, engine automatic extinguishing, engine fault lights and VSC fault lights on the instrument, AFS OFF warning lights flicker; the instrument display display "check VSC"; connect the diagnostic instrument, can not white move connection letter, through manual connection, display "and launch" and launch manual connection, display "and launch through manual connection. The machine ECU communication error ", and enter the system to read the fault code, without any relevant fault code. According to the phenomenon analysis, the possible reasons for the failure are: T ECM power circuit circuit breakage; 2 ECM grounding circuit breakage; OECM CAN communication line circuit breaker / short circuit fault; (4) ECM internal fault; 5 other related failures. Connect the diagnostics, check the CAN system, check all the control units and find that no ECM has been detected. Check the circuit according to the circuit diagram. Check the engine ECM A24 connector 20 pin voltage 12V. When the ignition switch is opened, the A24 connector No. 1 and the pin voltage of the 2- pin are 0V, indicating that the circuit of the EFI2 power supply control circuit is broken. So the test lamp is used to check the EFI2 fuse, both ends have the power output, and there is no fusing phenomenon. Is there a break between the outlet of the fuse connector and the A24 connector? So using the multimeter to detect the fuse to the A24 connector 2 pin resistance is 0.5 Omega indicating no circuit breakage, at this time restart the engine, running well, the vehicle is restored to normal. Troubleshooting: from the above inspection, it is known that the cause of the vehicle fault is the bad contact of the components such as the line or connector. It can be deduced that the bad contact line is between EFI2 1 and A24 connector, and the connection part is EFI2 fuse seat and A24 connector respectively. Check the pin of the A24 connector. The meter shows signs of deformation or corrosion, and the terminal connects the rabbit with jade. Check the EFI2 fuse holder and find a copper wire on the fuse pin, and the fuse holder has a melting carbonization phenomenon (as shown in Figure 2). Re connect to the fuse, and the engine sometimes becomes automatic again. At this time, the resistance of the fuse seat to the Lantau fuse is infinity. Due to the addition of the name of the raw Na, the operation is not standardized. When the connection line is cut off, a wire is not taken out, which leads to the bad contact between the EFI2 fuse and the seat, which leads to the loss of the fuse seat, which leads to the automatic extinguishing of the engine. As the fuse holder is damaged and no inventory parts are replaced, the fuse PAA foot is replaced to another empty seat, which is assembled for trial run and troubleshooting. Fault summary: from the above failure to inform us, in the daily maintenance, should standardize the operation, prevent human fault appearance; and inform the customer in the external installation of the harm of fine quality, may affect its driving safety.