What are the methods for testing automotive hydraulic solenoid valves?

The methods for testing automotive hydraulic solenoid valves are as follows:

(1) Connect the oil pressure gauge to the pressure tapping hole of the back pressure of the automatic transmission accumulator.

(2) Find the wiring pin of the control end of the hydraulic solenoid valve on the wiring harness plug of the automatic transmission computer according to the circuit diagram, and connect one leg of an 8W bulb to the pin of the control end of the hydraulic solenoid valve.

(3) Park the car on the ground, tighten the parking brake, and plug the four wheels with the triangular wood.

(4) Start the engine, check and adjust the engine idle speed.

(5) Press the brake pedal and place the shift lever in the forward position "D".

(6) Read the accumulator back pressure at this time, and its value should be greater than zero.

(7) Ground the other end of the 8W bulb connected to the hydraulic solenoid valve. At this time, the hydraulic solenoid valve will be energized to open, and the back pressure of the accumulator at this time will be read.