DTC P25B4-73: Turbocharger/Supercharger Wastegate "A" Actuator Stuck Closed [10/2015 - ]: Procedure

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CHECK ANY OTHER DTCS OUTPUT (IN ADDITION TO DTC P25B4-73)

Connect the Techstream to the DLC3.
Turn the engine switch on (IG).
Turn the Techstream on.
Enter the following menus: Powertrain / Engine / Trouble Codes.

Read the DTCs.

Powertrain > Engine > Trouble Codes

Result

Result	Proceed to
DTC P25B4-73 is output	A
DTC P25B4-73 and other DTCs are output	B

HINT:

If any DTCs other than P25B4-73 are output, troubleshoot those DTCs first.

Result:

GO TO DTC CHART. Refer to DIAGNOSTIC TROUBLE CODE CHART [10/2015 - 08/2016] , or refer to DIAGNOSTIC TROUBLE CODE CHART [08/2016 - 11/2017] , or refer to DIAGNOSTIC TROUBLE CODE CHART [11/2017 - 10/2018] , or refer to DIAGNOSTIC TROUBLE CODE CHART [10/2018 - 11/2019] , or refer to DIAGNOSTIC TROUBLE CODE CHART [11/2019 - 09/2020] , or refer to DIAGNOSTIC TROUBLE CODE CHART [09/2020 - 10/2022] , or refer to DIAGNOSTIC TROUBLE CODE CHART [10/2022 - ]

Result:

See step 2

CHECK VACUUM REGULATING VALVE ASSEMBLY

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

*1	Waste Gate Valve Actuator with Bracket Assembly

Disconnect the vacuum hose of the waste gate valve actuator with bracket assembly.
Start the engine.

Check whether the vacuum hose of the vacuum regulating valve assembly applies no suction your finger.

Vacuum hose applies no suction to finger.

Result

Proceed to
OK
NG

Result:

See step 22

Result:

See step 3

INSPECT WASTE GATE VALVE (TURBINE HOUSING WITH VALVE SUB-ASSEMBLY)

Inspect the waste gate valve.

Refer to PROCEDURE - Step 1

Result

Proceed to
OK
NG

Result:

See step 21

Result:

See step 4

INSPECT WASTE GATE VALVE ACTUATOR WITH BRACKET ASSEMBLY

Inspect the waste gate valve actuator with bracket assembly.

Refer to INSPECTION [10/2015 - ]

Result

Proceed to
OK
NG

Result:

See step 19

Result:

See step 5

INSPECT MASS AIR FLOW METER SUB-ASSEMBLY

Inspect the mass air flow meter sub-assembly, referring to On-vehicle Inspection for Mass Air Flow Meter.
Refer to ON-VEHICLE INSPECTION [10/2015 - ]
Inspect the mass air flow meter sub-assembly, referring to Inspection for Mass Air Flow Meter.
Refer to INSPECTION [10/2015 - ]

Inspect the operation of the mass air flow meter sub-assembly.

Connect the Techstream to the DLC3.
Start the engine.
Turn the Techstream on.

Enter the following menus: Powertrain / Engine / Data List / Engine Speed, Mass Air Flow Sensor and Coolant Temperature.

Powertrain > Engine > Data List

Tester Display
Engine Speed
Mass Air Flow Sensor
Coolant Temperature

Allow the engine to idle until Coolant Temperature reaches 75°C (167°F) or higher.

Read Mass Air Flow Sensor while maintaining an engine speed of 3000 rpm.

Standard

Techstream Display	Condition	Specified Condition
Mass Air Flow Sensor	Engine warmed up Shift lever position: P A/C: Off Engine Speed: 3000 rpm	Between 6.0 gm/sec and 18.0 gm/sec

Result

Proceed to
OK
NG

Result:

See step 14

Result:

See step 6

INSPECT NO. 2 TURBO PRESSURE SENSOR

Inspect the No. 2 turbo pressure sensor.

Refer to PROCEDURE - Step 1

Result

Proceed to
OK
NG

Result:

See step 9

Result:

See step 7

CHECK WHETHER DTC OUTPUT RECURS (DTC P25B4-73)

Connect the Techstream to the DLC3.
Turn the engine switch on (IG).
Turn the Techstream on.
Clear the DTCs.
Powertrain > Engine > Clear DTCs
Turn the engine switch off and wait for at least 30 seconds.
Start the engine and warm it up.
Turn the Techstream on.
Drive the vehicle in accordance with the driving pattern described in Confirmation Driving Pattern.

Enter the following menus: Powertrain / Engine / Utility / All Readiness.

Powertrain > Engine > Utility

Tester Display
All Readiness

Input the DTC: P25B4-73.

Check the DTC judgment result.

Result

Result	Proceed to
NORMAL (DTCs are not output)	A
ABNORMAL (DTC P25B4-73 is output)	B

Result:

CHECK FOR INTERMITTENT PROBLEMS. Refer to CHECK FOR INTERMITTENT PROBLEMS [10/2015 - ]

Result:

See step 8

REPLACE ECM

Replace the ECM.

Refer to REMOVAL [10/2015 - ]

Result

Proceed to
NEXT

Result:

See step 23

CHECK TERMINAL VOLTAGE (POWER SOURCE OF NO. 2 TURBO PRESSURE SENSOR)

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

*a	Front view of wire harness connector (to No. 2 Turbo Pressure Sensor)

Disconnect the No. 2 turbo pressure sensor connector.
Turn the engine switch on (IG).

Measure the voltage according to the value(s) in the table below.

Standard Voltage

Tester Connection	Condition	Specified Condition
F70-3 (VC) - F70-1 (E2)	Engine switch on (IG)	4.75 to 5.25 V
F70-2 (PTA) - F70-1 (E2)	Engine switch on (IG)	3.0 to 5.25 V

Result

Proceed to
OK
NG

Result:

See step 11

Result:

See step 10

REPLACE NO. 2 TURBO PRESSURE SENSOR

Replace the No. 2 turbo pressure sensor.

Refer to PROCEDURE - Step 2

Result

Proceed to
NEXT

Result:

See step 23

CHECK HARNESS AND CONNECTOR (NO. 2 TURBO PRESSURE SENSOR - ECM)

Disconnect the No. 2 turbo pressure sensor connector.
Disconnect the ECM connector.

Measure the resistance according to the value(s) in the table below.

Standard Resistance

Tester Connection	Condition	Specified Condition
F70-3 (VC) - F67-140 (VPTA)	Always	Below 1 Ω
F70-2 (PTA) - F67-108 (PTA)	Always	Below 1 Ω
F70-1 (E2) - F67-139 (EPTA)	Always	Below 1 Ω
F70-3 (VC) or F67-140 (VPTA) - Body ground and other terminals	Always	10 kΩ or higher
F70-2 (PTA) or F67-108 (PTA) - Body ground and other terminals	Always	10 kΩ or higher

Result

Proceed to
OK
NG

Result:

See step 13

Result:

See step 12

REPLACE ECM

Replace the ECM.

Refer to REMOVAL [10/2015 - ]

Result

Proceed to
NEXT

Result:

See step 23

REPAIR OR REPLACE HARNESS OR CONNECTOR

Repair or replace the wire harness or connector.

Result

Proceed to
NEXT

Result:

See step 23

CHECK TERMINAL VOLTAGE (POWER SOURCE OF MASS AIR FLOW METER SUB-ASSEMBLY)

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

*a	Front view of wire harness connector (to Mass Air Flow Meter Sub-assembly)

Disconnect the mass air flow meter sub-assembly connector.
Turn the engine switch on (IG).

Measure the voltage according to the value(s) in the table below.

Standard Voltage

Tester Connection	Condition	Specified Condition
F38-3 (+B) - Body ground	Engine switch on (IG)	11 to 14 V

Result

Proceed to
OK
NG

Result:

See step 17

Result:

See step 15

CHECK HARNESS AND CONNECTOR (MASS AIR FLOW METER SUB-ASSEMBLY - ECM)

Disconnect the mass air flow meter sub-assembly connector.
Disconnect the ECM connector.

Measure the resistance according to the value(s) in the table below.

Standard Resistance

Tester Connection	Condition	Specified Condition
F38-5 (VG) - F67-92 (VG)	Always	Below 1 Ω
F38-4 (E2G) - F67-91 (E2G)	Always	Below 1 Ω
F38-5 (VG) or F67-92 (VG) - Body ground and other terminals	Always	10 kΩ or higher

Result

Proceed to
OK
NG

Result:

See step 20

Result:

See step 16

REPLACE MASS AIR FLOW METER SUB-ASSEMBLY

Replace the mass air flow meter sub-assembly.

Refer to REMOVAL [10/2015 - ]

HINT:

Perform "Inspection After Repair" after replacing the mass air flow meter sub-assembly.

Refer to INITIALIZATION [10/2015 - 10/2018] , or refer to INITIALIZATION [10/2018 - 11/2019] , or refer to INITIALIZATION [11/2019 - ]

Result

Proceed to
NEXT

Result:

See step 23

CHECK HARNESS AND CONNECTOR (SEMICONDUCTOR PWR INTEGRATION ECU - MASS AIR FLOW METER SUB-ASSEMBLY)

Disconnect the semiconductor pwr integration ECU connector.
Disconnect the mass air flow meter sub-assembly connector.

Measure the resistance according to the value(s) in the table below.

Standard Resistance

Tester Connection	Condition	Specified Condition
2G-1 - F38-3 (+B)	Always	Below 1 Ω
2G-1 or F38-3 (+B) - Body ground and other terminals	Always	10 kΩ or higher

Result

Proceed to
OK
NG

Result:

See step 20

Result:

See step 18

REPLACE SEMICONDUCTOR POWER INTEGRATION ECU

Replace the semiconductor pwr integration ECU.

Refer to REMOVAL [09/2014 - ]

Result

Proceed to
NEXT

Result:

See step 23

REPLACE WASTE GATE VALVE ACTUATOR WITH BRACKET ASSEMBLY

Replace the waste gate valve actuator with bracket assembly.

Refer to REMOVAL [10/2015 - ]

Result

Proceed to
NEXT

Result:

See step 23

REPAIR OR REPLACE HARNESS OR CONNECTOR

Repair or replace the wire harness or connector.

Result

Proceed to
NEXT

Result:

See step 23

REPLACE TURBINE HOUSING WITH VALVE SUB-ASSEMBLY

Replace the turbine housing with valve sub-assembly.

Refer to REMOVAL [10/2015 - ]

Result

Proceed to
NEXT

Result:

See step 23

REPLACE VACUUM REGULATING VALVE ASSEMBLY

Replace the vacuum regulating valve assembly.

Refer to REMOVAL [10/2015 - ]

Result

Proceed to
NEXT

Result:

See step 23

CHECK WHETHER DTC OUTPUT RECURS (DTC P25B4-73)

Connect the Techstream to the DLC3.
Turn the engine switch on (IG).
Turn the Techstream on.
Clear the DTCs.
Powertrain > Engine > Clear DTCs
Turn the engine switch off and wait for at least 30 seconds.
Start the engine and warm it up.
Turn the Techstream on.
Drive the vehicle in accordance with the driving pattern described in Confirmation Driving Pattern.

Enter the following menus: Powertrain / Engine / Utility / All Readiness.

Powertrain > Engine > Utility

Tester Display
All Readiness

Input the DTC: P25B4-73.

Check the DTC judgment result.

Techstream Display	Description
NORMAL	DTC judgment completed System normal
ABNORMAL	DTC judgment completed System abnormal
INCOMPLETE	DTC judgment not completed Perform driving pattern after confirming DTC enabling conditions

Result

Proceed to
NEXT

Result:

END