Transmission Control Systems: Testing and Inspection

40/41TE PRE-DIAGNOSTIC TROUBLESHOOTING PROCEDURE

For a complete wiring diagram Consult Diagrams/Electrical.

- Many transmission symptoms can be caused by a low fluid level. If the fluid level is low, locate and repair any leaks and fill the transmission to the proper fluid level.
- Testing should only be performed with the battery fully charged to avoid false diagnosis.
- With the scan tool, read Engine (PCM) DTCs. If Engine DTCs are present, perform the appropriate diagnostic procedure(s) before proceeding.
- With the scan tool, read Transmission (TCM) DTCs. Record all Stored, Active, and Pending DTC information. Diagnose any Pending DTC as a matured DTC.
- With the scan tool, read and record any DTC EVENT DATA. Use this data to help identify the conditions in which the DTC was set.

Note: Performing a Battery Disconnect will clear all DTC EVENT DATA and may reset all learned Transmission values to the controllers default values, which could cause erratic shift schedules.

- With the scan tool, perform the Shift Lever Position Test. If the test does not pass, refer to the diagnostic procedure for P0706-Transmission Range Sensor Rationality.
- For Gear Ratio Error DTCs, use the scan tool to read and record the Clutch Volume Index (CVI) information.
- Refer to the When Monitored and Set Conditions for this DTC. DTCs can set at ignition on, at start up, driving under specific conditions, or after controller diagnostic monitors have run.
- Refer to applicable Technical Service Bulletins (TSBs) for controller software update information. Some conditions can be corrected by upgrading the Engine (PCM) or Transmission (TCM) controller software.
- Check for any Service Information Tune-ups or Service Bulletins for any possible causes that may apply.

Were there any repairs made that fixed the vehicle?

Yes

- Testing complete.
- Perform 40/41TE VERIFICATION TEST 40/41TE Transmission Verification Test

No

- Refer to the Transmission category and perform the appropriate diagnostic procedure(s).