1.通过试车确定故障的大致方向

1. Determine the approximate direction of the fault through a test drive

(1)如果油门加得越慢，冲击越大，这种情况显然不符合换挡控制逻辑，因此故障原因在信号方面，需要重点检查节气门位置信号和车速信号。

(1) If the throttle is applied slowly and the impact is greater, this situation obviously does not conform to the shift control logic. Therefore, the cause of the fault lies in the signal aspect, and it is necessary to focus on checking the throttle position signal and vehicle speed signal.

(2)如果每个挡都冲击，故障原因就在公共部分，包括油泵、阀体、主油路调节阀、节气门传感器、车速传感器以及控制模块。

(2) If every gear is impacted, the cause of the malfunction lies in the common parts, including the oil pump, valve body, main oil regulating valve, throttle sensor, vehicle speed sensor, and control module.

(3)如果只是个别挡冲击，故障原因应该在与该挡相关的部件上。

(3) If it is only an individual gear impact, the cause of the fault should be related to the components associated with that gear.

2.查询故障码和读取数据流

2. Query fault codes and read data streams

一辆2010款北京现代悦动汽车，行驶里程26000km，在行驶中自动变速器出现冲击现象，发动机故障指示灯(它与变速器故障指示灯合二为一)点亮。连接故障诊断仪，查询到变速器控制单元存储有故障码P0743，含义为DCC电磁阀对地断路，数据流显示变速器锁定在三挡。给DCC电磁阀通电试验，没有工作的声音，给其他4个电磁阀通电都工作正常，说明DCC电磁阀已经损坏。

A 2010 Beijing Hyundai Yuedong car with a mileage of 26000km experienced an automatic transmission shock during driving, and the engine malfunction indicator light (which is combined with the transmission malfunction indicator light) lit up. Connect the fault diagnosis instrument and check that there is a fault code P0743 stored in the transmission control unit, which means that the DCC solenoid valve is open to ground, and the data flow shows that the transmission is locked in third gear. When conducting a power test on the DCC solenoid valve, there was no sound of operation. However, when the other four solenoid valves were powered on and worked normally, it indicates that the DCC solenoid valve has been damaged.

自动变速箱维修

Automatic transmission maintenance

3.检查变速器油压是否过高或过低

3. Check if the transmission oil pressure is too high or too low

自动变速器换挡冲击的一个常见原因是油压不正常。以A341  E型自动变速器(凌志400汽车采用)为例，在怠速运转条件下，D位时主油路的标准油压为0.382～0.441 M  Pa，R位时主油路的标准油压为0.579～0.657MPa。

A common cause of gear shift shock in automatic transmissions is abnormal oil pressure. Taking the A341 E-type automatic transmission (adopted by the Lexus 400 car) as an example, under idle operation conditions, the standard oil pressure of the main oil circuit is 0.382-0.441 MPa in the D position and 0.579-0.657MPa in the R position.

在自动变速器的壳体上，有用螺塞封盖的油压检测孔。如果只有1个检测孔，它一定是主油路压力的检测孔;如果有多个检测孔，说明还可以通过它们检查节气门阀、离心调速器和执行器伺服装置的工作油压。

On the housing of the automatic transmission, there is an oil pressure detection hole covered with a screw plug. If there is only one detection hole, it must be the detection hole for the main oil circuit pressure; If there are multiple detection holes, it means that they can also be used to check the working oil pressure of the throttle valve, centrifugal governor, and actuator servo device.

4.检查节气门位置传感器的信号

4. Check the signal of the throttle position sensor

如果多个挡位出现换挡冲击，说明主油压过高，需要检查节气门位置传感器(TPS)的信号是否失常，还要检查加速踏板位置传感器、离合器速度传感器、电子节气门的工作情况。如果节气门的开度信号与发动机转速、车速之间不匹配，出现换挡冲击就在所难免了。

If there is shift shock in multiple gears, it indicates that the main oil pressure is too high. It is necessary to check whether the signal of the throttle position sensor (TPS) is abnormal, and also check the working condition of the accelerator pedal position sensor, clutch speed sensor, and electronic throttle. If the throttle opening signal does not match the engine speed and vehicle speed, gear shift shock is inevitable.

5.检查输入轴转速传感器是否失常

5. Check if the input shaft speed sensor is malfunctioning

输入轴转速传感器负责将涡轮轴的转速信号传输给TCM，以控制管路压力、变速器换挡模式以及变矩器离合器的结合与释放。输入轴转速信号同时用来近似计算工作齿轮的传动比以及变矩器离合器的打滑量。如果输入轴转速传感器的机械装配、相互位置、线路连接或者信号传送方面出现问题，就会导致换挡冲击现象。

The input shaft speed sensor is responsible for transmitting the speed signal of the turbine shaft to the TCM to control pipeline pressure, transmission shift mode, and the engagement and release of the torque converter clutch. The input shaft speed signal is used to approximate the transmission ratio of the working gear and the slip of the torque converter clutch. If there are problems with the mechanical assembly, mutual position, wiring connection, or signal transmission of the input shaft speed sensor, it can lead to gear shift shock phenomenon.

6.检查减振器工作是否正常

6. Check if the shock absorber is working properly

在自动变速器中，每个前进挡都有一个对应的减振器，它与该挡的换挡阀至换挡执行元件间的油路相通。当自动变速器换挡时，来自换挡阀

In an automatic transmission, each forward gear has a corresponding damper, which is connected to the oil circuit between the shift valve and the shift actuator of that gear. When the automatic transmission shifts, it comes from the shift valve