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DTC P0731-P0734

Diagnostic Instructions
    • Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
    • Review Strategy Based Diagnosis for an overview of the diagnostic approach.
    • Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptors

DTC P0731 : Incorrect 1st Gear Ratio

DTC P0732 : Incorrect 2nd Gear Ratio

DTC P0733 : Incorrect 3rd Gear Ratio

DTC P0734 : Incorrect 4th Gear Ratio

Circuit/System Description

When driving in the D position, the actual gear ratio in the each gear range deviated from the target gear ratio toward the higher input speed or the actual gear ratio deviated toward the lower input speed.

The related input and output signals are normal with no information on malfunctions.

Therefore, it is necessary to check each if the gear engagement elements in the control valve and inside the transmission.

Conditions for Running the DTC

P0731

    • Transmission is in Drive range.
    • Vehicle speed is more than 10 km/h (6 mph).
    • Input speed is more than 1,000 RPM.
    • Throttle position is greater than 25 percent.
    • The voltage of the transmission fluid temperature sensor is between 0.1 and 2.4 V.
    • The temperature of the TFT sensor is between 20° C (68° F) and 100° C (212° F).
    • Engine speed is greater than 460 RPM.

P0732

    • Transmission is in Drive range.
    • Vehicle speed is more than 20 km/h (12 mph).
    • Input speed is more than 1,000 RPM.
    • Throttle position is greater than 13 percent.
    • The voltage of the transmission fluid temperature sensor is between 0.1 and 2.4 V.
    • The temperature of the TFT sensor is between 20° C (68° F) and 100° C (212° F).
    • Engine speed is greater than 460 RPM.

P0733

    • Transmission is in Drive range.
    • Vehicle speed is more than 40 km/h (25 mph).
    • Input speed is more than 1,000 RPM.
    • Throttle position is greater than 13 percent.
    • The voltage of the transmission fluid temperature sensor is between 0.1 and 2.4V.
    • The temperature of the TFT sensor is between 20°C (68°F) and 100°C (212°F).
    • Engine speed is greater than 460 RPM.

P0734

    • Transmission is in Drive range.
    • Vehicle speed is more than 45 km/h (28 mph).
    • Input speed is more than 1,000 RPM.
    • Throttle position is greater than 13 percent.
    • The voltage of the transmission fluid temperature sensor is between 0.1 and 2.4 V.
    • The temperature of the TFT sensor is between 20° C (68° F) and 100° C (212° F).
    • Engine speed is greater than 460 RPM.

Conditions for Setting the DTC

Absolute value for Input speed minus input shaft revolution is greater than 500 RPM.

Action Taken When the DTC Sets

DTCs P0731, P0732, P0733 and P0734 are Type B DTC.

Conditions for Clearing the DTC

DTCs P0731, P0732, P0733 and P0734 are Type B DTC.

Diagnostic Aids

Improper transmission fluid level may cause DTC P0731, P0732, P0733 and P0734 to set. Refer to the Transmission Fluid Level Inspection procedure.

Reference Information

Description and Operation

    •  Transmission General Description
    •  Transmission Component and System Description

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification
  1. Ignition ON, observe the DTC information with a scan tool.
  2. Record Freeze Frame and Failure Records.
  3. Clear DTCs.
  4. Operate the vehicle under the conditions observed in the Failure Records.
  5. Observe the DTC information with the scan tool. Verify that DTC P0731-P0734 does not set.

Circuit/System Testing
  1. Perform the oil pressure when idling and stalling. Refer to Line Pressure Check procedure.
    2. ⇒If not within the specified range, repair as necessary.
  2. Inspect for the inside of the transmission after removing the valve body cover in order to know the extent of the damage.
    3. ⇒If there is any problem, remove the transmission and inspect the inside of it.
  3. Inspect for the following conditions and repair/replace as necessary:
    4. • The low clutch for malfunction
    • The low one way clutch for malfunction
    • The 2-4 brake for malfunction
    • The high clutch for malfunction
    • The control valve body for malfunction
    • The parts related to the internal transmission powerflow for malfunction
    ⇒If the inside of the transmission is seriously damaged, replace the transmission.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

    •  Line Pressure Check
    •  Transmission Fluid Level Inspection
    •  Low Clutch Disassemble
    •  Low Clutch Assemble
    •  High Clutch Disassemble
    •  High Clutch Assemble
    •  Transmission Disassemble
    •  Transmission Assemble
    •  Control Valve Body Replacement
    •  Control Valve Body Disassemble
    •  Control Valve Body Assemble
    •  Transmission Replacement
   


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