Diagnostic Aids

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When attempting to set transmission performance DTCs, observe the Freeze Frame and Failure Records to assist in duplicating the failure conditions.
If diagnosing a P0776 DTC and you know the 3-5-R Clutch is not stuck On, inspect for a sticking clutch select valve 2.
If by shifting to reverse you obtain a neutral state, PC Sol. 2 could be stuck off. Perform a Control Solenoid Valve and Transmission Control Module Assembly Solenoid Performance Test to verify the solenoid is stuck off.
If by shifting to neutral you obtain a reverse state, PC Sol. 2 could be stuck on. Perform a Control Solenoid Valve and Transmission Control Module Assembly Solenoid Performance Test to verify the solenoid is stuck on.
Use the scan tool to view the TFP Switch status and refer to the Transmission Fluid Pressure Switch Logic table to determine when a TFP switch should be active or inactive for a given gear. This will help to determine if the hydraulic circuit functioning and if the PC solenoid or the valve train is in an incorrect position.