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Initial Inspection and Diagnostic Overview






42RLE - PRE-DIAGNOSTIC TROUBLESHOOTING PROCEDURE

For a complete wiring diagram Refer to the Wiring Information.

Perform the following steps prior to any diagnostic procedure(s).

NOTE: Due to different power control configurations, the Transmission Control Relay (if equipped) may be referred to as a PCM relay.

1. 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. Refer to the Service Information for the proper repair and fluid fill procedures.
2. Testing should only be performed with the battery fully charged to avoid false diagnosis.
3. With the scan tool check pinion factor (if equipped) for proper tire identification and program or reprogram if necessary.
4. With the scan tool, read Engine (PCM) DTCs. If Engine DTCs are present, refer to the Driveability Category and perform to the appropriate diagnostic procedure(s) before proceeding.
5. With the scan tool, read Transmission (TCM) DTCs. Record all Stored, Active, and Pending DTC information. Diagnose any Pending DTC as a matured DTC.
6. With the scan tool, read and record any Event Data. Use this data to help identify the conditions in which the DTC was set.

NOTE: Event Data may exist even if no DTCs are stored. Clearing DTCs does NOT erase the Event Data. To erase Event Data information you must either with the scan tool perform a Quick Learn procedure, Quick Learn Procedure battery disconnect (if available), or manually disconnect the battery. Whatever method used can reset some learned transmission values to controller defaults. This may cause poor shift quality until those values are relearned.Most DTCs require two "bad trips" before they are stored and the MIL illuminates. The transmission may enter "limp-in" mode during the first bad trip. However, if the fault condition is not present in the next ignition cycle and a "good trip" has been completed, the one trip or "pending" DTC may be cleared. The pending DTC information will be stored in the Event Data even though the scan tool shows no DTCs present. If the customer reports a limp-in event and no DTCs are present, check the Event Data.

7. 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. P0706
8. For Gear Ratio Error DTCs, use the scan tool to read and record the Clutch Volume Index (CVI) information.
9. Use the wiring diagram as a guide, inspect the wiring and connectors related to this circuit and repair as necessary.
10. Refer to the When Monitored and Set Conditions for this DTC. DTCs can set at ignition on, at start up, driving under specific conditions, and after controller diagnostic monitors have run.
11. 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.
12. Check for any Service Information Tune-ups or Service Bulletins for any possible causes that may apply.

Did any of the above procedures repair the vehicle?

Yes

- Testing is complete.
- Perform 42RLE TRANSMISSION VERIFICATION TEST. Transmission Verification Test

No

- Perform the appropriate diagnostic procedure(s).
- Testing and Inspection