Diagnostic Procedure

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

CHECK FOR RELATED DTCS
1. Ignition on, engine off.
2. Using the scan tool, check DTCs.
  Are there any Speed Sensor and/or TCC DTCs present?
  
  Yes
  - See DTC-Based Diagnostics/MODULE, Transmission Control (TCM) - Diagnosis and Testing and perform the appropriate diagnostic procedure.
  No
  - Go to step 2
CHECK THE TORQUE CONVERTER CLUTCH PERFORMANCE
1. Operate the vehicle until the transmission sump temperature is to greater than 65° C (150° F).
2. Using the shifter lever, select third gear.
3. Accelerate the vehicle to third gear and hold.
4. With the scan tool, verify the TCC status is reading "SLIP".
5. Monitor TCC Desired Slip and TCC Actual Slip.
6. Operate the vehicle at 30 mph while maintaining third gear.
7. Lightly depress the accelerator and hold the throttle position steady between 40 and 50%.
8. Slowly accelerate vehicle using steady throttle without causing TCC Status to read "OPEN".
  NOTE: If at any time during the above test the TCC Status changes from SLIP to OPEN, or the vehicle downshifts to a lower gear, the test is invalid and must be performed again.
9. Compare TCC Actual Slip and TCC Desired Slip during steady throttle acceleration with TCC Status continually reading "SLIP".
  Does TCC Actual Slip exceed TCC Desired Slip by more than 60 rpm while accelerating at a steady throttle and staying in SLIP mode?
  
  Yes
  - Inspect transmission fluid for water contamination. Refer to Transmission and Transfer Case/Automatic - NAG1/FLUID and FILTER - Diagnosis and Testing .
  - Inspect internal transmission. Pay particular attention to the components related to the TCC such as possible missing Input Shaft Seal Ring, Lockup Control Valve sticking in its bore, and/or a leaking TCC Solenoid.
  - If no internal transmission issues found, replace the Torque Converter. Refer to Transmission and Transfer Case/Automatic - NAG1/TORQUE CONVERTER - Removal .
  - Perform the NAG1 TRANSMISSION VERIFICATION TEST. See DTC-Based Diagnostics/MODULE, Transmission Control (TCM) - Standard Procedure .
  No
  - Go to step 3
TRANSMISSION CONTROL MODULE (TCM)
1. Using the schematics as a guide, check the Transmission Control Module (TCM) pins, terminals, and connectors for corrosion, damage, or terminal push out. Pay particular attention to all power and ground circuits. Check for Service Bulletins for any possible causes that may apply. If no problems are found, replace and program the TCM in accordance with the Service Information. Refer to Electrical/Electronic Control Modules/MODULE, Transmission Control - Removal .
2. Perform TCC slip test to verify repair.
  NOTE: To set P0741 fault, TCM must encounter three events where the TCM cannot control TCC Actual Slip to TCC Desired Slip in a single key cycle.
  
  Does the DTC reset?
  
  Yes
  - Inspect transmission fluid for water contamination. Refer to Transmission and Transfer Case/Automatic - NAG1/FLUID and FILTER - Diagnosis and Testing .
  - Inspect internal transmission. Pay particular attention to the components related to the TCC such as possible missing Input Shaft Seal Ring, Lockup Control Valve sticking in its bore, and/or a leaking TCC Solenoid.
  - If no internal transmission issues are found, replace the Torque Converter in accordance with the Service Information. See DTC-Based Diagnostics/MODULE, Transmission Control (TCM) - Standard Procedure .
  - Perform the NAG1 TRANSMISSION VERIFICATION TEST. See DTC-Based Diagnostics/MODULE, Transmission Control (TCM) - Standard Procedure .
  No
  - Test complete.