DTC P0731:00 [FN4A-EL]

id050218817800

DTC P0731:00

Gear 1 incorrect ratio

DETECTION CONDITION

•  Under the following conditions, the gear ratio in 1GR is 2.19 or less for 1 s four times.

―  Accelerator pedal position is 4.53% or more

―  Time since selector lever changing to D or M position is 10 s or more

―  Vehicle is driven without shifting

―  ATF temperature is 20 °C {68 °F} or more

―  Engine speed is 300 rpm or more

―  Turbine speed is 225 to 4,987 rpm

―  Output shaft speed is 35 rpm or more

―  DTCs relating TR switch are not stored

―  DTCs relating input/turbine speed sensor are not stored

―  DTCs relating TFT sensor are not stored

―  DTCs relating shift solenoid A are not stored

―  DTCs relating shift solenoid B are not stored

―  DTCs relating shift solenoid C are not stored

―  DTCs relating shift solenoid D are not stored

―  DTCs relating shift solenoid E are not stored

Diagnostic support note

•  The check engine light does not illuminate.

•  The automatic transaxle warning light illuminates if the PCM detects the above malfunction condition during the first drive cycle.

•  PENDING CODE is not available.

•  FREEZE FRAME DATA is not available.

•  The DTC is stored in the PCM memory.

POSSIBLE CAUSE

•  Deteriorated ATF

•  ATF level low

•  Solenoid valve malfunction

―  Pressure control solenoid

―  Shift solenoid A

•  Line pressure malfunction

•  Stall speed malfunction

•  Forward clutch slipping

•  One-way clutch slipping

•  Control valve body malfunction

•  PCM malfunction

DTC P0731:00	Gear 1 incorrect ratio
DETECTION CONDITION	• Under the following conditions, the gear ratio in 1GR is 2.19 or less for 1 s four times. ― Accelerator pedal position is 4.53% or more ― Time since selector lever changing to D or M position is 10 s or more ― Vehicle is driven without shifting ― ATF temperature is 20 °C {68 °F} or more ― Engine speed is 300 rpm or more ― Turbine speed is 225 to 4,987 rpm ― Output shaft speed is 35 rpm or more ― DTCs relating TR switch are not stored ― DTCs relating input/turbine speed sensor are not stored ― DTCs relating TFT sensor are not stored ― DTCs relating shift solenoid A are not stored ― DTCs relating shift solenoid B are not stored ― DTCs relating shift solenoid C are not stored ― DTCs relating shift solenoid D are not stored ― DTCs relating shift solenoid E are not stored Diagnostic support note • The check engine light does not illuminate. • The automatic transaxle warning light illuminates if the PCM detects the above malfunction condition during the first drive cycle. • PENDING CODE is not available. • FREEZE FRAME DATA is not available. • The DTC is stored in the PCM memory.
POSSIBLE CAUSE	• Deteriorated ATF • ATF level low • Solenoid valve malfunction ― Pressure control solenoid ― Shift solenoid A • Line pressure malfunction • Stall speed malfunction • Forward clutch slipping • One-way clutch slipping • Control valve body malfunction • PCM malfunction

Diagnostic procedure

STEP	INSPECTION		ACTION
1	VERIFY RELATED REPAIR INFORMATION AVAILABILITY • Verify related Service Information availability. • Is any related repair information available?	Yes	Perform repair or diagnosis according to the available repair information. • If the vehicle is not repaired, go to the next step.
1		No	Go to the next step.
2	INSPECT ATF CONDITION • Inspect the ATF condition. (See AUTOMATIC TRANSAXLE FLUID (ATF) INSPECTION [FN4A-EL].) • Is it normal?	Yes	Go to the next step.
2		No	Replace the ATF, then go to Step 9. (See AUTOMATIC TRANSAXLE FLUID (ATF) REPLACEMENT [FN4A-EL])
3	INSPECT ATF LEVEL • Inspect the ATF level. (See AUTOMATIC TRANSAXLE FLUID (ATF) INSPECTION [FN4A-EL].) • Is it normal?	Yes	Go to the next step.
3		No	Add ATF to the specified level, then go to Step 9. (See AUTOMATIC TRANSAXLE FLUID (ATF) REPLACEMENT [FN4A-EL])
4	INSPECT SOLENOID VALVE • Inspect the following solenoid valves: (See SOLENOID VALVE INSPECTION [FN4A-EL].) ― Pressure control solenoid ― Shift solenoid A • Is there any malfunction?	Yes	Replace the solenoid valve, then go to Step 9. (See SOLENOID VALVE REMOVAL/INSTALLATION [FN4A-EL].)
4		No	Go to the next step.
5	INSPECT LINE PRESSURE • Perform the “Line Pressures Test”. (See MECHANICAL SYSTEM TEST [FN4A-EL].) • Is there any malfunction?	Yes	Repair or replace malfunctioning part according to test result, then go to Step 9.
5		No	Go to the next step.
6	INSPECT STALL SPEED • Perform the “Stall Test”. (See MECHANICAL SYSTEM TEST [FN4A-EL].) • Is there any malfunction?	Yes	Repair or replace malfunctioning part according to test result, then go to Step 9.
6		No	Go to the next step.
7	INSPECT TURBINE SPEED WHILE DRIVING VEHICLE • Connect the M-MDS. • Start the engine. • Measure the PID “TSS” while driving vehicle under the following conditions: ― Selector lever position: D or M position ― Gear position: 1GR ― Vehicle speed: 20 km/h {12 mph} • Is the PID “TSS”approx.2,150 RPM?	Yes	Go to Step 9.
7		No	Go to the next step.
8	INSPECT CONTROL VALVE BODY • Remove the control valve body. (See CONTROL VALVE BODY REMOVAL/INSTALLATION [FN4A-EL].) • Disassemble the control valve body. • Inspect the following parts: ― Shift valve ― Return spring ― Hydraulic passage • Is there any malfunction?	Yes	Repair or replace malfunctioning part according to inspection result, then go to next step.
8		No	Replace the transaxle, then go to the next step. (See AUTOMATIC TRANSAXLE REMOVAL/INSTALLATION [FN4A-EL].)
9	VERIFY DTC TROUBLESHOOTING COMPLETED • Make sure to reconnect all the disconnected connectors. • Clear the DTC using the M-MDS. • Perform the following procedure to ensure that the DTC has been resolved: 1. Drive the vehicle in 1GR under the following conditions for 1 s or more. ― Accelerator pedal position is 4.53% or more ― Time since selector lever changing to D or M position is 10 s or more ― Vehicle is driven without shifting ― ATF temperature (PID item: TFT) is 20 °C {68 °F} or more ― Engine speed (PID item: RPM) is 300 rpm or more ― Turbine speed (PID item: TSS) is 225 to 4,987 rpm ― Output shaft speed (PID item: OSS) is 35 rpm or more 2. Stop the vehicle. 3. Repeat Step 1—2 three times. • Is the same DTC present?	Yes	Replace the PCM, then go to the next step. (See PCM REMOVAL/INSTALLATION [FN4A-EL].)
9		No	Go to the next step.
10	VERIFY NO DTCs ARE PRESENT • Perform the “Reading DTCs Procedure”. (See ON-BOARD DIAGNOSTIC SYSTEM DTC INSPECTION [FN4A-EL].) • Are any DTCs present?	Yes	Go to the applicable DTC inspection. (See ON-BOARD DIAGNOSTIC SYSTEM DTC TABLE [FN4A-EL].)
10		No	DTC troubleshooting completed.