Diagnostic Test

1. With the scan tool, check for other transmission DTCs.

   Are there any Transmission line pressure, speed sensor, and/or loss of prime DTCs present?

   Yes 

   • Is the only related DTC present P0933-00? If yes, go to  2
   • If any of these DTCs are present, they may cause a Speed Ratio Error. Perform the test for P0944-00 first if it is present. and perform the appropriate diagnostic procedure. Refer to DIAGNOSTIC CODE INDEX .

   No 

   • Go To  2

1. With the scan tool, read and record the Event Data.
   NOTE:

   Make sure to record all Event Data stored in the scan tool for future reference in this test procedure.

   Does the Event Data display information for the DTC P0734-00?

   Yes 

   • Go To  4

   No 

   • Go To  3

1. In the Event Data, identify the DTC that was recorded earlier.

   Does the Event Data display information for the DTC P1790-00, with target gear = 4th, or with both OD and UD clutches applying?

   Yes 

   • Go To  4

   No 

   • Go To  7

1. Refer to the Event Data recorded earlier.

   Does the Input RPM read zero?

   Yes 

   • Check the input speed sensor and wiring. Refer to test P0716 and diagnose as if the DTC is current. Refer to DIAGNOSTIC CODE INDEX .

   No 

   • Go To  5

1. Refer to the Event Data recorded earlier.

   Is the line pressure reading more than 10 psi below the desired line pressure?

   Yes 

   • Go To  6

   No 

   • Go To  7

1. Turn the ignition off.
2. Remove and inspect the Transmission Oil Pan for excessive debris in accordance with the Service Information.
3. Remove and inspect the Primary Oil Filter in accordance with the Service Information.
   NOTE:

   Make sure the Primary Transmission Oil Filter and seal are properly installed and are not cracked or split.

   NOTE:

   This transmission is equipped with a solenoid for the Torque Converter Clutch (TCC) that is a Variable Force Solenoid (VFS) with close tolerance Pressure/Inductance (PI) curve. It is necessary to update the TCC solenoid PI data in the PCM when replacing the TCC solenoid, Valve Body or Transmission assembly. This is done with the scan tool using the "Program Torque Converter Solenoid PI Curve" routine. The PI data is located on a 2-D BAR code etched on the body of the TCC solenoid. The data must be entered into the scan tool in order to upload the information to the PCM.

   When replacing the TCC solenoid or Valve Body, obtain the PI data before installing the transmission oil pan. When replacing the transmission, the PI data can be obtained from a 2-D bar code on the exterior of the new transmission. Early build transmissions will have the 2-D barcode label on the right side of the transmission case. Late build transmissions will have the label attached to a machined pad at the top of the case, near the rear of the transmission. If it is suspected that the valve body or TCC VFS has been replaced without uploading the correct PI data into the PCM, the transmission oil pan must be removed to retrieve the information from the 2-D bar code on the body of the TCC solenoid.

   Does the Oil Pan contain excessive debris and/or is the Primary Oil Filter cracked, plugged or mis-installed?

   Yes 

   • Repair the plugged, cracked, or split Primary Transmission Oil Filter and/or seal. If excessive clutch debris is present, check the clutches for damage. Refer to the Service Information for the proper hydraulic clutch repair procedure.
   • If the Valve Body or the TCC VFS solenoid is replaced, remove the external TCC VFS bar code label from the transmission case.
   • Perform the TRANSMISSION VERIFICATION TEST. Refer to TRANSMISSION VERIFICATION TEST .

   No 

   • Remove the Transmission Oil Pump in accordance with the Service Information. Check the main Regulator Valve for sticking in its bore, scoring, and/or damage and clean and repair as necessary. If no problem is found, replace the Transmission Solenoid/TRS Assembly.
   • Perform the TRANSMISSION VERIFICATION TEST. Refer to TRANSMISSION VERIFICATION TEST .

1. With the scan tool, perform the Direct Gear Clutch Test. Follow the instructions on the scan tool.
2. Increase the throttle angle, TPS Degree, to 30° for no more than a few seconds.
   CAUTION:

   Do not overheat the transmission.

   NOTE:

   If the OD clutch is faulty, the overrunning clutch will hold and the slip test will pass. The Direct gear clutch test will not detect a faulty OD clutch. However, it will detect a faulty UD clutch.

   Did the clutch test pass, did the Input Speed remain at zero?

   Yes 

   • Go To  8

   No 

   • Go To  10

1. Check the Shifter adjustment in accordance with the Service Information.
   NOTE:

   Intermittent gear ratio DTCs can be set by problems in the Input and Output Speed Sensor circuits and/or Speed Sensor Ground circuit.

2. Check the Speed Sensor wiring and connectors for good connection.

   Were there any problems found?

   Yes 

   • Repair as necessary.
   • Perform the TRANSMISSION VERIFICATION TEST. Refer to TRANSMISSION VERIFICATION TEST .

   No 

   • Go To  9

1. With the scan tool, erase Transmission DTCs.
2. Road test the vehicle. Check operation in all forward gears and Reverse.
3. If slippage is detected, check whether the line pressure is more than 10 psi below the desired line pressure reading on the scan tool.
4. Check and record any transmission DTCs.
5. Disconnect the Transmission Solenoid/TRS Assembly harness connector to induce Limp-in.
6. Again test drive the vehicle and check the transmission operation in Drive and Reverse while in Limp-in.
7. Note whether Drive Limp-in provides 1st gear or 4th (direct) gear.
8. Reconnect all disconnected connectors and erase any Transmission DTCs.

   Perform the appropriate procedure that best describes your road test results:

   No obvious slippage noted in any gear 

   Go To  15.

   Obvious slippage noted in one or more gears, and line pressure (actual) is often more than 10 psi below the Desired Line Pressure reading on the scan tool 

   • Go To  6

   Slippage noted in 4th gear and Drive Limp-in provides 1st gear 

   • Go To  12

   Slippage noted in Reverse gear and Drive Limp-in provides 1st gear 

   • Replace the Transmission Solenoid/TRS Assembly in accordance with the Service Information. Refer to ASSEMBLY, TRANSMISSION SOLENOID AND TRS, REMOVAL AND INSTALLATION .
   • Perform the TRANSMISSION VERIFICATION TEST. Refer to TRANSMISSION VERIFICATION TEST .

   Slippage noted in 4th gear while Drive Limp-in allows 4th gear WITHOUT slippage 

   • Replace the Transmission Solenoid/TRS Assembly in accordance with the Service Information. Refer to ASSEMBLY, TRANSMISSION SOLENOID AND TRS, REMOVAL AND INSTALLATION .
   • Perform the TRANSMISSION VERIFICATION TEST. Refer to TRANSMISSION VERIFICATION TEST .

   All other possible conditions 

   • Go To  12

1. Remove Transmission Oil Pan and check for excessive debris.
2. Remove the Valve Body and air check the UD hydraulic clutch circuit (in the case) in accordance with the Service Information.
   NOTE:

   The UD clutch passage contains a small bleed orifice, a small amount of air leakage is normal.

   Were there any problems found, excessive debris and/or excessive air leakage in the UD hydraulic clutch circuit?

   Yes 

   NOTE:

   This transmission is equipped with a solenoid for the Torque Converter Clutch (TCC) that is a Variable Force Solenoid (VFS) with close tolerance Pressure/Inductance (PI) curve. It is necessary to update the TCC solenoid PI data in the PCM when replacing the TCC solenoid, Valve Body or Transmission assembly. This is done with the scan tool using the "Program Torque Converter Solenoid PI Curve" routine. The PI data is located on a 2-D BAR code etched on the body of the TCC solenoid. The data must be entered into the scan tool in order to upload the information to the PCM.

   When replacing the TCC solenoid or Valve Body, obtain the PI data before installing the transmission oil pan. When replacing the transmission, the PI data can be obtained from a 2-D bar code on the exterior of the new transmission. Early build transmissions will have the 2-D barcode label on the right side of the transmission case. Late build transmissions will have the label attached to a machined pad at the top of the case, near the rear of the transmission. If it is suspected that the valve body or TCC VFS has been replaced without uploading the correct PI data into the PCM, the transmission oil pan must be removed to retrieve the information from the 2-D bar code on the body of the TCC solenoid.

   • Repair as necessary. Check the UD clutch piston seals, reaction shaft support seal rings and dribbler assemblies, and the flatness of the pump valve body and pump housing faces. Check main regulator valve for sticking in the bore.
   • If the Valve Body or the TCC VFS solenoid is replaced, remove the external TCC VFS bar code label from the transmission case.
   • If the UD clutch has failed but no obvious cause is found (such as a cut piston seal, broken seal ring, low line pressure in DTC Event Data, etc.) replace the Transmission Solenoid/TRS Assembly in addition to any necessary internal repairs.
   • Perform the TRANSMISSION VERIFICATION TEST. Refer to TRANSMISSION VERIFICATION TEST .

   No 

   • Go To  11

1. Check the UD bleed orifice, accumulator piston, and accumulator piston seal in the main valve body.

   Were there any problems found?

   Yes 

   NOTE:

   This transmission is equipped with a solenoid for the Torque Converter Clutch (TCC) that is a Variable Force Solenoid (VFS) with close tolerance Pressure/Inductance (PI) curve. It is necessary to update the TCC solenoid PI data in the PCM when replacing the TCC solenoid, Valve Body or Transmission assembly. This is done with the scan tool using the "Program Torque Converter Solenoid PI Curve" routine. The PI data is located on a 2-D BAR code etched on the body of the TCC solenoid. The data must be entered into the scan tool in order to upload the information to the PCM.

   When replacing the TCC solenoid or Valve Body, obtain the PI data before installing the transmission oil pan. When replacing the transmission, the PI data can be obtained from a 2-D bar code on the exterior of the new transmission. Early build transmissions will have the 2-D barcode label on the right side of the transmission case. Late build transmissions will have the label attached to a machined pad at the top of the case, near the rear of the transmission. If it is suspected that the valve body or TCC VFS has been replaced without uploading the correct PI data into the PCM, the transmission oil pan must be removed to retrieve the information from the 2-D bar code on the body of the TCC solenoid.

   • Repair as necessary. Refer to the Service Information for proper repair procedures.
   • If the Valve Body or the TCC VFS solenoid is replaced, remove the external TCC VFS bar code label from the transmission case.

   No 

   • Replace Transmission Solenoid/TRS Assembly in accordance with the Service Information. Refer to ASSEMBLY, TRANSMISSION SOLENOID AND TRS, REMOVAL AND INSTALLATION .
   • Perform the TRANSMISSION VERIFICATION TEST. Refer to TRANSMISSION VERIFICATION TEST .

1. Remove the Transmission Oil Pan and check for excessive debris.
2. Remove the valve body and check if the accumulator cover is intact.
3. Air check the OD hydraulic clutch circuit (in the case) in accordance with the Service Information.
   NOTE:

   The OD clutch passage contains a small bleed orifice which connects to the Reverse clutch hydraulic circuit, a small amount of air leakage into the Reverse clutch passage is normal.

   Were there any problems found, excessive debris, and/or excessive air leakage in the OD hydraulic clutch circuit?

   Yes 

   NOTE:

   This transmission is equipped with a solenoid for the Torque Converter Clutch (TCC) that is a Variable Force Solenoid (VFS) with close tolerance Pressure/Inductance (PI) curve. It is necessary to update the TCC solenoid PI data in the PCM when replacing the TCC solenoid, Valve Body or Transmission assembly. This is done with the scan tool using the "Program Torque Converter Solenoid PI Curve" routine. The PI data is located on a 2-D BAR code etched on the body of the TCC solenoid. The data must be entered into the scan tool in order to upload the information to the PCM.

   When replacing the TCC solenoid or Valve Body, obtain the PI data before installing the transmission oil pan. When replacing the transmission, the PI data can be obtained from a 2-D bar code on the exterior of the new transmission. Early build transmissions will have the 2-D barcode label on the right side of the transmission case. Late build transmissions will have the label attached to a machined pad at the top of the case, near the rear of the transmission. If it is suspected that the valve body or TCC VFS has been replaced without uploading the correct PI data into the PCM, the transmission oil pan must be removed to retrieve the information from the 2-D bar code on the body of the TCC solenoid.

   • Repair as necessary. Refer to the Service Information for proper repair procedures. Note: Check the bleed orifice in the OD/Reverse clutch piston.
     NOTE:

     If the OD clutch has failed but no obvious cause is found (such as a cut piston seal, broken seal ring, low line pressure in DTC Event Data, etc.) replace the Transmission Solenoid/TRS Assembly in addition to any necessary internal repairs.

   • If the Valve Body or the TCC VFS solenoid is replaced, remove the external TCC VFS bar code label from the transmission case.
   • Perform the TRANSMISSION VERIFICATION TEST. Refer to TRANSMISSION VERIFICATION TEST .

   No 

   • Go To  13

1. Check the OD Accumulator piston for cracks or a cut seal.
2. Check the Solenoid Switch Valve and its plugs for sticking in its bore or excessive wear.

   Were there any problems found?

   Yes 

   NOTE:

   This transmission is equipped with a solenoid for the Torque Converter Clutch (TCC) that is a Variable Force Solenoid (VFS) with close tolerance Pressure/Inductance (PI) curve. It is necessary to update the TCC solenoid PI data in the PCM when replacing the TCC solenoid, Valve Body or Transmission assembly. This is done with the scan tool using the "Program Torque Converter Solenoid PI Curve" routine. The PI data is located on a 2-D BAR code etched on the body of the TCC solenoid. The data must be entered into the scan tool in order to upload the information to the PCM.

   When replacing the TCC solenoid or Valve Body, obtain the PI data before installing the transmission oil pan. When replacing the transmission, the PI data can be obtained from a 2-D bar code on the exterior of the new transmission. Early build transmissions will have the 2-D barcode label on the right side of the transmission case. Late build transmissions will have the label attached to a machined pad at the top of the case, near the rear of the transmission. If it is suspected that the valve body or TCC VFS has been replaced without uploading the correct PI data into the PCM, the transmission oil pan must be removed to retrieve the information from the 2-D bar code on the body of the TCC solenoid.

   • Repair as necessary. Refer to the Service Information for proper repair procedures.
   • If the Valve Body or the TCC VFS solenoid is replaced, remove the external TCC VFS bar code label from the transmission case.
   • Perform the TRANSMISSION VERIFICATION TEST. Refer to TRANSMISSION VERIFICATION TEST .

   No 

   • Go To  14

1. Remove the Transmission in accordance with the Service Information and inspect the OD shaft and its spline to the reverse carrier hub.
   NOTE:

   This transmission is equipped with a solenoid for the Torque Converter Clutch (TCC) that is a Variable Force Solenoid (VFS) with close tolerance Pressure/Inductance (PI) curve. It is necessary to update the TCC solenoid PI data in the PCM when replacing the TCC solenoid, Valve Body or Transmission assembly. This is done with the scan tool using the "Program Torque Converter Solenoid PI Curve" routine. The PI data is located on a 2-D BAR code etched on the body of the TCC solenoid. The data must be entered into the scan tool in order to upload the information to the PCM.

   When replacing the TCC solenoid or Valve Body, obtain the PI data before installing the transmission oil pan. When replacing the transmission, the PI data can be obtained from a 2-D bar code on the exterior of the new transmission. Early build transmissions will have the 2-D barcode label on the right side of the transmission case. Late build transmissions will have the label attached to a machined pad at the top of the case, near the rear of the transmission. If it is suspected that the valve body or TCC VFS has been replaced without uploading the correct PI data into the PCM, the transmission oil pan must be removed to retrieve the information from the 2-D bar code on the body of the TCC solenoid.

   Were there any problems found?

   Yes 

   • Repair as necessary.

   No 

   • Disassemble and inspect the input clutch assembly. Check the OD and Reverse clutch seals, discs, and bleed orifice (in the OD/Reverse clutch piston). Check the OD hub and shaft. Repair as necessary. Refer to the Service Information for proper repair procedures.
     NOTE:

     If the OD clutch has failed but no obvious cause is found (such as a cut piston seal, broken seal ring, stuck regulator valve, etc.), replace the Transmission Solenoid/TRS Assembly in addition to any other necessary repairs.

   • If the Valve Body or the TCC VFS solenoid is replaced, remove the external TCC VFS bar code label from the transmission case.
   • Perform the TRANSMISSION VERIFICATION TEST. Refer to TRANSMISSION VERIFICATION TEST .

Did the DTC P0734-00 reset during the road test?

Yes 

• Go To  16

No 

• Go To  17

1. If any other DTCs set during the road test, refer to the appropriate symptom in the Transmission diagnostic information.
2. If no other DTCs set during the road test, below is a list of possible causes, but not strictly limited to those.
3. Check for:
   • Excessive debris in the Transmission Oil pan, plugged, cracked, or mis-installed Primary Transmission Oil Filter and/or seal.
   • OD and UD accumulator pistons and seals and bleed orifices, and the Solenoid Switch Valve and Plugs in the main valve body.
   • OD and UD clutch piston seals, reaction shaft support seal rings and dribbler assemblies, and the flatness of the pump valve body and pump housing faces.
   • Main regulator valve for sticking in its bore.

   Repair 

   NOTE:

   This transmission is equipped with a solenoid for the Torque Converter Clutch (TCC) that is a Variable Force Solenoid (VFS) with close tolerance Pressure/Inductance (PI) curve. It is necessary to update the TCC solenoid PI data in the PCM when replacing the TCC solenoid, Valve Body or Transmission assembly. This is done with the scan tool using the "Program Torque Converter Solenoid PI Curve" routine. The PI data is located on a 2-D BAR code etched on the body of the TCC solenoid. The data must be entered into the scan tool in order to upload the information to the PCM.

   When replacing the TCC solenoid or Valve Body, obtain the PI data before installing the transmission oil pan. When replacing the transmission, the PI data can be obtained from a 2-D bar code on the exterior of the new transmission. Early build transmissions will have the 2-D barcode label on the right side of the transmission case. Late build transmissions will have the label attached to a machined pad at the top of the case, near the rear of the transmission. If it is suspected that the valve body or TCC VFS has been replaced without uploading the correct PI data into the PCM, the transmission oil pan must be removed to retrieve the information from the 2-D bar code on the body of the TCC solenoid.

   • Repair as necessary. Refer to the Service Information for proper repair procedures.
     NOTE:

     If the OD or UD clutch has failed but no obvious cause is found (such as a cut piston seal, broken seal ring, stuck regulator valve, or other items listed above) replace the Transmission Solenoid/TRS Assembly in addition to any necessary internal repairs.

   • If the Valve Body or the TCC VFS solenoid is replaced, remove the external TCC VFS bar code label from the transmission case.
   • Perform the TRANSMISSION VERIFICATION TEST. Refer to TRANSMISSION VERIFICATION TEST .

1. The conditions to set this DTC are not currently present.
2. With the scan tool, check the Event Data to help identify the conditions in which the DTC was set.
   NOTE:

   This transmission is equipped with a solenoid for the Torque Converter Clutch (TCC) that is a Variable Force Solenoid (VFS) with close tolerance Pressure/Inductance (PI) curve. If replacing the PCM, it is necessary to transfer the PI data from the old PCM to the new PCM using the scan tool. If the PCM being replaced is non-responsive, the PI data can be retrieved from a 2-D bar code on the exterior of the transmission case. This is done with the scan tool using the "Program Torque Converter Solenoid PI Curve" routine.

   Early build transmissions will have the 2-D barcode label on the right side of the transmission case. Late build transmissions will have the label attached to a machined pad at the top of the case, near the rear of the transmission. The data must be entered into the scan tool in order to upload the information to the PCM. In the event that the exterior BAR code is missing, or it is suspected that the valve body or TCC solenoid has been replaced without uploading the correct PI data into an existing PCM, the transmission oil pan must be removed to retrieve the information from the 2-D bar code on the body of the TCC solenoid.

   • If the DTC Event Data shows fault P0734-00 was set in the Park, Reverse, or Neutral, replace the Powertrain Control Module. Refer to REMOVAL AND INSTALLATION .
   NOTE:

   This transmission is equipped with a solenoid for the Torque Converter Clutch (TCC) that is a Variable Force Solenoid (VFS) with close tolerance Pressure/Inductance (PI) curve. It is necessary to update the TCC solenoid PI data in the PCM when replacing the TCC solenoid, Valve Body or Transmission assembly. This is done with the scan tool using the "Program Torque Converter Solenoid PI Curve" routine. The PI data is located on a 2-D BAR code etched on the body of the TCC solenoid. The data must be entered into the scan tool in order to upload the information to the PCM.

   When replacing the TCC solenoid or Valve Body, obtain the PI data before installing the transmission oil pan. When replacing the transmission, the PI data can be obtained from a 2-D bar code on the exterior of the new transmission. Early build transmissions will have the 2-D barcode label on the right side of the transmission case. Late build transmissions will have the label attached to a machined pad at the top of the case, near the rear of the transmission. If it is suspected that the valve body or TCC VFS has been replaced without uploading the correct PI data into the PCM, the transmission oil pan must be removed to retrieve the information from the 2-D bar code on the body of the TCC solenoid.

   • If the DTC Event Data shows fault P0734-00 set with input RPM = zero, check the input speed sensor and related wiring.
   • If the DTC Event Data shows fault P0734-00 set with line pressure significantly below desired line pressure, check for the cause of low line pressure (i.e., oil level, misinstalled or damaged primary filter or filter seal, sticking main regulator valve in pump, etc.).
   • If the DTC Event Data shows fault P0734-00 set with the OD or UD pressure switch open (but line pressure matches Desired Line Pressure), air check the OD and UD hydraulic clutch circuits for leakage in accordance with the Service Information. If the OD and UD hydraulic clutch circuits are OK, replace the Transmission Solenoid/TRS assembly.
   • If the Valve Body or the TCC VFS solenoid is replaced, remove the external TCC VFS bar code label from the transmission case.
3. Check the gearshift linkage adjustment.
4. Intermittent Gear Ratio DTCs can be set by problems in the Input and Output Speed Sensor circuits and/or Speed Sensor Ground circuit.
5. Wiggle wiring and connectors while checking for intermittent operation with the Transmission Simulator.
6. Gear ratio DTCs can also be set under extreme temperature conditions.
7. Verify if the problem is only experienced under extreme hot or cold conditions.

   Were there any problems found.

   Yes 

   • Repair as necessary.
   • Perform the TRANSMISSION VERIFICATION TEST. Refer to TRANSMISSION VERIFICATION TEST .

   No 

   • Test Complete.