A Dongfeng Honda CR-V with a mileage of about 79 thousand km and a 5 speed automatic transmission is configured in 2010. After an accident, the car changed the gearbox of the front. After the assembly was completed, the vehicle found that there was a larger vibration when all the gears were up and down, and then the D indicator flashed. Fault diagnosis: 1) according to the fault situation, the possible causes of the fault are: (1) automatic transmission clutch pressure control solenoid valve B fault. 2. Automatic transmission clutch pressure control solenoid valve C failure. (3) the failure of the speed sensor of the transmission shaft (spindle). (4) the fault of the oil temperature sensor of the automatic transmission. There are foreign objects in the throttle hole of the separation plate. 2) as the D indicator flickers, there is a fault code. First use HDS to read automatic transmission fault code, show P0777: automatic transmission clutch pressure control solenoid valve B card lag in the open position; P0796: automatic transmission (A/T) clutch pressure control solenoid valve C card hysteresis in the closed position. 3) remove the fault code, re read the fault code, and display it as the P07% fault code. 4) in the D bit, take a road test at least 20 20s, at least 20s, then slow down until the vehicle stops. 5) in the DTC / freeze data under the automatic transmission mode menu, monitoring the DTC P0796 in the OBD state shows that it is not passed. 6) use HDS to clear the DTC. 7) select the clutch pressure control solenoid valve C in the sub detection menu (Miscellaneous Test Menu), and use HDS to test the clutch pressure of the automatic transmission to control the solenoid valve C, showing that the solenoid valve is abnormal. 8) disconnect the C plug of the solenoid valve and check the resistance between the terminals 1 and 2 is 1 ohm (standard value 3~10 Ohm), indicating the clutch pressure control solenoid valve C fault. 9) replace the automatic transmission clutch pressure control solenoid valve C, test run, accelerate good, troubleshooting.