DESCRIPTION
The power management control ECU uses the B1 and B2 brakes in the hybrid vehicle transmission assembly to switch between low and high gear.
Shifting control is performed using the line pressure circuit, B1 circuit, and B2 circuit. The power management control ECU detects abnormal line pressure by monitoring the operation of the oil pressure switch and oil pressure sensor in each circuit.
Tech Tips
Although the DTC title indicates an incorrect gear ratio, DTC P0731-871 relates to a malfunction of the B2 hydraulic circuit.
Tech Tips
The preceding timing chart is for the first "Control the Shift Position" Active Test. The chart will differ for the second or later "Control the Shift Position" Active Test.
If "Hi" is selected in the first "Control the Shift Position" Active Test, it may take more time to shift to "Hi".
DTC No. | INF Code | DTC Detection Condition | Trouble Area |
---|---|---|---|
P0731 | 871 | Even if the fluid pressure was applied for low gear after the ST-on state occurred, the power management control ECU is not able to confirm that the fluid pressure was applied to the B2 circuit within the specified time. |
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Tech Tips
ST-on is a state that occurs when the READY indicator in the combination meter blinks after the power switch is pressed with the brake pedal depressed.
WIRING DIAGRAM
INSPECTION PROCEDURE
PROCEDURE
CHECK DTC OUTPUT (HYBRID CONTROL)
Connect the GTS to the DLC3.
Turn the power switch on (IG).
Enter the following menus: Powertrain / Hybrid Control / Trouble Codes.
Check if DTCs are output.
Result | ||||||
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DTC No. | Relevant Diagnosis |
---|---|
P0748-850 | Pressure Control Solenoid "A" Electrical (Shift Solenoid Valve (SL1)) |
P0778-851 | Pressure Control Solenoid "B" Electrical (Shift Solenoid Valve (SL2)) |
P06A4-209 | Sensor Reference Voltage "D" Circuit Low |
P06A5-210 | Sensor Reference Voltage "D" Circuit High |
Turn the power switch off.
B |
GO TO DTC CHART (HYBRID CONTROL SYSTEM) Click here |
A |
CHECK CONNECTOR CONNECTION CONDITION (POWER MANAGEMENT CONTROL ECU CONNECTOR)
*A | for LHD |
*B | for RHD |
Check the connector connections and contact pressure of the relevant terminals for the power management control ECU connectors Click here.
OK |
---|
The connectors are connected securely and there are no contact pressure problems. |
NG |
CONNECT SECURELY |
OK |
CHECK CONNECTOR CONNECTION CONDITION (TRANSMISSION WIRE CONNECTOR)
Check the connection of the transmission wire connector Click here.
OK |
---|
The connector is connected securely and there are no contact problems. |
NG |
CONNECT SECURELY |
OK |
READ VALUE USING GTS (POWER SUPPLY SENSOR VOLTAGE)
Connect the GTS to the DLC3.
Turn the power switch on (IG).
Enter the following menus: Powertrain / Hybrid Control / Data List / Power Supply Sensor Voltage.
Read the Data List.
OK | ||||||
---|---|---|---|---|---|---|
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Turn the power switch off.
NG |
REPLACE POWER MANAGEMENT CONTROL ECU Click here |
OK |
CHECK POWER MANAGEMENT CONTROL ECU (VOLTAGE)
*a | Front view of wire harness connector (to Oil Pressure Sensor) |
Disconnect the oil pressure sensor connector.
Turn the power switch on (IG).
Measure the voltage according to the value(s) in the table below.
Standard Voltage | ||||||
---|---|---|---|---|---|---|
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Turn the power switch off.
Connect the oil pressure sensor connector.
NG |
CHECK HARNESS AND CONNECTOR (POWER MANAGEMENT CONTROL ECU - OIL PRESSURE SENSOR) Click here |
NG |
READ VALUE USING GTS (B2 OIL PRESSURE SENSOR)
*a | Front view of wire harness connector (to Oil Pressure Sensor) |
Disconnect the oil pressure sensor connector.
Connect the GTS to the DLC3.
Turn the power switch on (IG).
Enter the following menus: Powertrain / Hybrid Control / Data List / B2 Oil Pressure Sensor.
Read the Data List.
OK | ||||||||
---|---|---|---|---|---|---|---|---|
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Turn the power switch off.
Connect the oil pressure sensor connector.
NG |
CHECK HARNESS AND CONNECTOR (POWER MANAGEMENT CONTROL ECU - OIL PRESSURE SENSOR) Click here |
OK |
CHECK HYBRID VEHICLE TRANSMISSION ASSEMBLY (SOLENOID VALVE (SL1), SOLENOID VALVE (SL2))
*a | Rear view of wire harness connector (to Power Management Control ECU) |
Disconnect the power management control ECU connector.
Measure the resistance according to the value(s) in the table below.
Standard Resistance | |||||||||
---|---|---|---|---|---|---|---|---|---|
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Connect the power management control ECU connector.
NG |
CHECK HARNESS AND CONNECTOR (TRANSMISSION WIRE) Click here |
OK |
CHECK HYBRID VEHICLE TRANSMISSION ASSEMBLY (OIL PRESSURE SENSOR)
*a | Rear view of wire harness connector (to Power Management Control ECU) |
Disconnect the connector from the power management control ECU.
Measure the resistance according to the value(s) in the table below.
Standard Resistance | |||||||||
---|---|---|---|---|---|---|---|---|---|
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Connect the power management control ECU connector.
NG |
REPLACE OIL PRESSURE SENSOR Click here |
OK |
CLEAR DTC
Connect the GTS to the DLC3.
Turn the power switch on (IG).
Enter the following menus: Powertrain / Hybrid Control / Trouble Codes.
Read and record the DTCs and freeze frame data.
Clear DTCs and freeze frame data.
Turn the power switch off.
NEXT |
CHECK DTC OUTPUT (HYBRID CONTROL)
Connect the GTS to the DLC3.
Turn the power switch on (READY).
Enter the following menus: Powertrain / Hybrid Control / Trouble Codes.
Check if DTCs are output.
Result | ||||||
---|---|---|---|---|---|---|
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Note
This DTC is not output when the power switch is on (IG). Therefore, make sure to perform the inspection with the power switch on (READY).
Turn the power switch off.
B |
REPLACE HYBRID VEHICLE TRANSMISSION ASSEMBLY Click here |
A |
CHECK FLUID LEAKS
Check for fluid leaks from the hybrid vehicle transmission assembly.
OK |
---|
There are no fluid leaks. |
NG |
REPAIR OR REPLACE HYBRID VEHICLE TRANSMISSION ASSEMBLY Click here |
OK |
CHECK FOR INTERMITTENT PROBLEMS Click here
CHECK HARNESS AND CONNECTOR (POWER MANAGEMENT CONTROL ECU - OIL PRESSURE SENSOR)
*a | Rear view of wire harness connector (to Power Management Control ECU) |
*b | Front view of wire harness connector (to Oil Pressure Sensor) |
Disconnect the oil pressure sensor connector.
Disconnect the power management control ECU connector.
Measure the resistance according to the value(s) in the table below.
Standard Resistance | |||||||||||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
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Connect the oil pressure sensor connector.
Connect the power management control ECU connector.
NG |
REPAIR OR REPLACE HARNESS OR CONNECTOR |
OK |
REPLACE POWER MANAGEMENT CONTROL ECU Click here
CHECK HARNESS AND CONNECTOR (TRANSMISSION WIRE)
*a | Front view of wire harness connector (to Transmission Wire) |
Disconnect the transmission wire connector.
Turn the power switch on (IG).
Measure the voltage according to the value(s) in the table below.
Standard Voltage | |||||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
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Note
Turning the power switch on (IG) with the transmission wire connector disconnected causes other DTCs to be stored. Clear the DTCs after performing this inspection.
Turn the power switch off.
Measure the resistance according to the value(s) in the table below.
Standard Resistance | |||||||||||||||||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
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Connect the transmission wire connector.
NG |
REPAIR OR REPLACE HARNESS OR CONNECTOR |
OK |
REPLACE HYBRID VEHICLE TRANSMISSION ASSEMBLY Click here
REPLACE HYBRID VEHICLE TRANSMISSION ASSEMBLY
NEXT |
REPLACE POWER MANAGEMENT CONTROL ECU Click here