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Control Solenoid Valve and Transmission Control Module Assembly Solenoid Performance Test

Special Tools

The purpose of this procedure is to test the control solenoid valve assembly solenoids for a stuck open or stuck closed condition, or a faulty transmission fluid pressure switch. DT-47825 test block is bolted to the control solenoid valve assembly on the valve body mounting surface. Pressurised air is passed into the aluminium test block, through the control solenoid valve assembly solenoid passage and back to the outlet port on the test block. A scan tool is used to command the solenoids ON and OFF. While observing the airflow, one can check the valve function. The recommended shop air pressure for this test is regulated to 90-100 psi.

Preliminary Procedures

1. Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle .
2. Remove the control solenoid valve assembly from the transmission. Refer to Control Solenoid Valve and Transmission Control Module Assembly Removal .
3. Perform the Control Solenoid Valve and Transmission Control Module Assembly Inspection procedure.

Caution: To avoid solenoid overheating and possible internal damage, do not continuously operate the solenoid for more than 2 minutes at a time. Drain the TCM of excess transmission fluid before attaching to test block and use caution when attaching air to test block air inlet.

Note: With the Vehicle in Service Mode and the engine OFF, the transmission control module will normally cycle some of the transmission solenoids On and Off to facilitate keeping the ports and solenoids clean and free of debris. This dither function is a normal activity and will cause the valves to cycle open and closed quickly when the TCM is powered up. This may cause some air to exit the ports where the pressure gauge is not connected as those solenoids cycle on and off.

1. Connect the DT-47825-20 adaptor harness to the vehicle harness (3) and the control solenoid valve assembly.
2. If necessary, clean each side of the filter plate assembly and install the filter plate assembly back on the control solenoid valve assembly. Clean the mounting surface of the DT-47825 test block .
3. Bolt the DT-47825 test block to the control solenoid valve assembly mounting surface. Use the bolts and washers supplied with the tool to attach the test block. Tighten the bolts to 5 N·m (44 lb in).
4. Connect the DT-47825-20 adaptor harness supplied with the DT-47825 test kit to the vehicle harness and to the Q8 control solenoid valve assembly. Engage the connector locks.
5. Vehicle in Service Mode.
6. Cover the DT-47825 test block ports (6) with a shop towel. Transmission fluid may exit these ports when the solenoids are commanded ON.
7. Connect regulated shop air (4) to the DT-47825 test block air inlet. Do not exceed the recommended air pressure of 620.5-689.4 kPa (90-100 psi).
8. Vehicle in Service Mode and the scan tool (1) connected to the DLC connector (2) communicating with the vehicle, command the solenoid in question ON and OFF. Observe the airflow at the appropriate test port for a change as you command the solenoid. Refer to Control Solenoid Valve Assembly Solenoid Performance Test Block to Component Identification for correct solenoid function and test block port connections for the solenoid being tested.
9. The solenoid should allow air pressure to flow or prevent air pressure flow depending on the solenoid state. The test results are read on the pressure gauge (5).
10. Command the solenoid valve ON and OFF several times to determine the condition of the solenoid in question. Release the test air pressure from the pressure the gauge between solenoid tests.

1. Remove the DT-47825 test block from the Q8 control solenoid valve assembly.
2. With the Vehicle in Service Mode and the scan tool communicating with the vehicle, using a soft blunt object, depress each transmission fluid pressure switch port. The corresponding transmission fluid pressure switch parameter on the scan tool display should display HI when depressed and Low when released.

⇒	If the Q8 control solenoid valve assembly fails any of the above tests, replace the Q8 control solenoid valve assembly.

⇒	If the Q8 control solenoid valve assembly passes the above tests, the problem is internal to the transmission.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Control Module References for Control Solenoid Valve Assembly and Transmission Control Module replacement, programming, and setup.