Control Solenoid Valve and Transmission Control Module Assembly Input Shaft Speed/Output Shaft Speed Input Test

Control Solenoid Valve and Transmission Control Module Assembly Input Shaft Speed/Output Shaft Speed Input Test

Special Tools
* EL 35616 - GM-Approved Terminal Test Kit
* EL 38522 - Variable Signal Generator

For equivalent regional tools, refer to Special Tools (6T70/6T75 - Automatic Transmission).





The purpose of this test is to provide a simulated input/output speed sensor (ISS/OSS) signal to the control solenoid valve assembly ISS/OSS input circuits.

Transmission Input Speed Sensor
1. Ignition OFF, disconnect the ISS wiring harness connector X3 (1) from the control solenoid valve assembly.
2. Ignition ON, test for 8.3-9.3 volts at terminal A.

• If not within the specified range, replace the control solenoid valve assembly. Refer to Control Solenoid Valve and Transmission Control Module Assembly Replacement (6T70/6T75 - Automatic Transmission).

3. Ignition OFF, using the EL 35616 - terminal test kit, connect the EL38522 - variable signal generator red lead to the ISS signal circuit terminal B on the TCM.
4. Connect the black lead from the EL 38522 - variable signal generator to ground.
5. Set the EL 38522 - variable signal generator to 5 volts, the frequency to 300 Hz, and the percent duty cycle to 50 or the normal position.
6. Ignition ON, verify with a scan tool the Transmission ISS parameter is between 495-505 RPM.

If not within the specified range, replace the control solenoid valve assembly. Refer to Control Solenoid Valve and Transmission Control Module Assembly Replacement (6T70/6T75 - Automatic Transmission).

Transmission Output Speed Sensor
1. Ignition OFF, disconnect the OSS wiring harness connector X4 (2) from the control solenoid valve assembly.
2. Ignition ON, test for 8.3-9.3 volts at terminal A.

• If not within the specified range, replace the control solenoid valve assembly. Refer to Control Solenoid Valve and Transmission Control Module Assembly Replacement (6T70/6T75 - Automatic Transmission).

3. Ignition OFF, using the EL 35616 - terminal test kit, connect the EL 38522 - variable signal generator red lead to the OSS signal circuit terminal B on the TCM.
4. Connect the black lead from the EL 38522 - variable signal generator to ground.
5. Set the EL 38522 - variable signal generator to 5 volts, the frequency to 300 Hz, and the percent duty cycle to 50 or the normal position.
6. Ignition ON, verify with a scan tool the Transmission OSS parameter is between 256-266 RPM.

• If not within the specified range, replace the control solenoid valve assembly. Refer to Control Solenoid Valve and Transmission Control Module Assembly Replacement (6T70/6T75 - Automatic Transmission).