Troubleshooting method of automatic transmission's failure to upshift

The automatic transmission cannot be upshifted. Please refer to: 1 for troubleshooting steps. Look at the computer fault code of the gearbox first to see if there is any permanent fault. The sensors to be inspected mainly include: throttle position sensor, vehicle speed sensor, engine speed sensor, etc. 2. Focus on reading the data flow of the throttle position sensor, and check the cable adjustment of the cable throttle. 3. Measure the oil pressure of the gearbox governor. If the oil pressure is low when the throttle is high, it is determined that the oil leakage needs to be repaired. 4. If the gearbox system still does not upshift without fault code, it is necessary to disassemble the gearbox to check whether there is wear and whether the gearbox oil pressure is reached. 5. Disassemble the gearbox valve body and check whether each shift valve body is damaged, dirty and stuck. Check whether there is any leakage in the brake oil circuit and piston with compressed gas.