Initial Inspection and Diagnostic Overview

PRE-DIAGNOSTIC CHECK OUT

Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding Pre-Diagnostic Troubleshooting Procedure.

For a complete wiring diagram Refer to Wiring Information.
PRE-DIAGNOSTIC CHECK OUT

NOTE: Low fluid level can be the cause of many transmission problems. If the fluid level is low locate and repair the leak then check and adjust the fluid level.

NOTE: Always perform diagnostics with a fully charged battery to avoid false symptoms.

1. With a scan tool, check for engine Diagnostic Trouble Codes (DTCs). Check and repair all engine DTCs prior to performing transmission symptom diagnostics.
2. With a scan tool, read transmission DTCs. Record all DTCs and 1 Trip Failures.

NOTE: Diagnose 1 Trip Failures as a fully matured DTC.

3. Using the wiring diagram/schematic as a guide, inspect the wiring harnesses and connectors and repair as necessary.
4. Perform the Shift Lever Position Test. If the test does not pass, P0706 for Symptom test P0706 Check Shifter Signal.
5. For Gear Ratio DTCs, check and record all CVIs.
6. Most DTCs set on start up, but some must be set by driving the vehicle to ensure that all diagnostic monitors have run.

NOTE: Verify flash level of the engine controller. Some problems are corrected by software upgrades to the transmission and engine systems.

NOTE: Due to the integration of the engine and transmission control modules, if a controller flash is performed it is also necessary to perform Quick Learn and Drive Learn procedures with a scan tool. Failure to do so may result in shift quality complaints.

NOTE: Check for applicable Service Bulletins that may apply.

Were any repairs made that corrected the concern?

Yes

- Testing complete.

No

- Refer to the diagnostic test procedure related to the DTC Testing and Inspection.