Circuit/System Testing

WARNING: This page is about a different variant/trim than selected.

Observe the scan tool Transmission OSS parameter while driving the vehicle. The reading should correspond to a known properly functioning OSS.
- If the OSS is malfunctioning, replace the Transmission Output Speed Sensor (OSS). refer to the Output Speed Sensor Replacement procedure.
Stop the vehicle, apply the parking brake, engine at idle, select P (park) using the Shift Control.
Observe the scan tool Transmission ISS parameter. The reading should be within 400-800 RPM.
- If the ISS parameter is not within the specified range, replace the Transmission Input Speed Sensor (ISS). Refer to the Input Speed Sensor Replacement procedure.
Firmly apply the brake, select D (drive) using the Shift Control.
Observe the scan tool TCC Slip Speed. The reading should be within 0-100 RPM.
- If the TCC Slip Speed is not within the specified range:
  - Ignition ON, engine OFF, command shift solenoid 1 ON and OFF with a scan tool. The solenoid should click when commanded ON.
    - If the solenoid does not click, replace the 1st shift solenoid valve assembly. Refer to Control Valve Body Assembly Disassemble .
  - Command shift solenoid 3 ON and OFF with a scan tool. The solenoid should click when commanded ON.
    - If the solenoid does not click, replace the 1-2, 2-3, reverse shift solenoid valve assembly. Refer to Control Valve Body Assembly Disassemble .
  - Perform a line pressure test. Refer to Line Pressure Check procedure.
  - Remove the control valve body cover. Refer to Control Valve Body Cover Removal procedure.
  - Inspect the inside of the control valve body cover for excessive sediment. There should not be excessive sediment.
    - If excessive sediment is found inspect and replace as necessary the second coast clutch, second clutch, forward clutch, and 1-2 reverse clutch. Refer to Fluid Pump Cleaning and Inspection ,2nd Clutch Assemble , Forward and Direct Clutch Assembly Assemble , and 1-2 Reverse Clutch Assemble procedures.
  - Inspect the control valve body assembly for the following conditions. The conditions should not be found.
    - Stuck U1 shift valve
    - Stuck M1 shift valve
    - Stuck U2 shift valve
    - Stuck shift pressure relay valve
    - Stuck neutral relay valve
    - Stuck line pressure control solenoid valve assembly
      refer to Control Valve Rear Body Disassemble and Control Valve Body Disassemble - Middle .
      - If any of the above conditions are found, replace the valve body assembly. Refer to Control Valve Body Replacement procedure.
  - Verify that the control valve body has been serviced within the past 3 months.
    - If the control valve body has not been serviced, replace the control valve body assembly. Refer to Control Valve Body Replacement procedure.
  - If all circuits and components test normal, replace the transmission.
If all circuits and components test normal, replace the transmission.