Diagnostic Test
- CHECK FOR RELATED DTCS
- With the scan tool, check for transmission DTCs.
- If any of these DTCs are present, perform their respective tests first.
Are Transmission solenoid, line pressure, speed sensor and/or loss of prime DTCs present?
Yes
- Refer to DIAGNOSIS AND TESTING and perform the appropriate diagnostic procedure. If any of these DTCs are present, they may cause a Gear Ratio Error. Perform the test for P0944 first, if present.
No
- Go To 2
- CHECK EVENT DATA
- CHECK THE TARGET GEAR
In the Event Data recorded earlier, does the Event Data show DTC P1790, with Target gear = 5th or with both the 2C and OD clutches applying?
Yes
- Go To 4
No
- Go To 6
- CHECK INPUT RPM
In the Event Data recorded earlier, does the Input rpm read zero?
Yes
- Refer to DIAGNOSIS AND TESTING . Perform the diagnostic procedure for P0716. Diagnose the DTC as if it is set and current.
No
- Go To 5
- CHECK LINE PRESSURE READING
In the Event Data recorded earlier, is the line pressure reading more than 10 psi below the desired line pressure reading?
Yes
- Remove the Transmission Oil pan and check the Transmission Oil filter for improper installation or plugged, if Primary oil filter is OK, check the main regulator valve in pump. If excessive debris is in the oil pan, check clutches and repair as necessary.
- Perform the TRANSMISSION VERIFICATION TEST. Refer to STANDARD PROCEDURE .
No
- Go To 6
- CHECK TRANSMISSION FOR SLIPPAGE
- CHECK IF DTC RESETS
- With the scan tool, check for transmission DTCs after the road test.
Did DTC P0735 reset?
Yes
- Go To 8
No
- Test Complete.
- Perform the TRANSMISSION VERIFICATION TEST. Refer to STANDARD PROCEDURE .
- With the scan tool, check for transmission DTCs after the road test.
- CHECK INTERNAL TRANSMISSION
- Remove the Transmission Oil Pan and Valve Body, in accordance with the Service Information, and check for the following:
- Excessive clutch and or metal debris in the oil pan.
- If the accumulator cover is intact and the 2C tower seal is not cut or split.
- OD and 2C accumulator pistons for cracks or cut seals.
- Solenoid Switch Valve and Plugs for stickiness or wear.
- Cut or missing No. 5, No. 6, or No. 7 check ball.
- OD bleed orifice on top of the valve body.
- Air check the OD and 2C hydraulic clutch circuits for excessive leakage. Refer to the Service information.
NOTE:Both the OD and 2C hydraulic clutch circuits contain a small bleed orifice. A small amount of air leakage is considered normal. The OD hydraulic clutch circuit bleed orifice connects to the Reverse input clutch hydraulic cavity. A small amount of air leakage into the Reverse hydraulic clutch circuit is considered normal.
Were any problems found?
Yes
- Repair as necessary.NOTE:
If the OD or 2C clutch has failed but no obvious cause is found (such as a cut piston seal, broken seal ring, stuck regulator valve or any other items listed above) replace the Transmission Solenoid/TRS Assembly in addition to any necessary internal repairs.
- Perform the TRANSMISSION VERIFICATION TEST. Refer to STANDARD PROCEDURE .
No
- Replace Transmission Solenoid/TRS Assembly in accordance with the Service Information.
- Perform the TRANSMISSION VERIFICATION TEST. Refer to STANDARD PROCEDURE .
- Remove the Transmission Oil Pan and Valve Body, in accordance with the Service Information, and check for the following: