Toyota Corolla Cross: Generator Inverter Actuator Stuck Closed (P0A7A73)

DTC SUMMARY

MALFUNCTION DESCRIPTION

This DTC is stored when a short is detected in the inverter with converter assembly (generator inverter) or the hybrid vehicle transaxle assembly (generator (MG1)). The cause of this malfunction may be one of the following:

Internal inverter malfunction

• Generator inverter internal circuit malfunction

Hybrid vehicle transaxle assembly (generator (MG1)) malfunction

• Open or short circuit
• Damage from iron particles or other foreign objects

DESCRIPTION

For a description of the inverter.

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DTC No.	Detection Item	DTC Detection Condition	Trouble Area	MIL	Warning Indicate	Note
P0A7A73	Generator Inverter Actuator Stuck Closed	Current flow to any phase of the generator (MG1) exceeds the threshold after the generator inverter is shut down due to a DTC indicating a generator inverter malfunction (overheating, overcurrent or circuit malfunction) being stored. (1 trip detection logic)	Inverter with converter assembly Motor cable Hybrid vehicle transaxle assembly	Comes on	Master Warning: Comes on	SAE Code: P0A7A

MONITOR DESCRIPTION

The motor generator control ECU monitors the generator inverter electric current. If the current exceeds the threshold for a specified period of time, the motor generator control ECU will illuminate the MIL and store a DTC.

MONITOR STRATEGY

Related DTCs	P0A7A (INF P0A7A73): GFIV detection (Short circuit malfunction)
Required sensors/components	Generator inverter
Frequency of operation	Continuous
Duration	TMC's intellectual property
MIL operation	1 driving cycle
Sequence of operation	None

TYPICAL ENABLING CONDITIONS

The monitor will run whenever the following DTCs are not stored	TMC's intellectual property
Other conditions belong to TMC's intellectual property	-

TYPICAL MALFUNCTION THRESHOLDS

TMC's intellectual property

-

COMPONENT OPERATING RANGE

Motor generator control ECU

DTC P0A7A (INF P0A7A73) is not detected

CONFIRMATION DRIVING PATTERN

HINT:

• After repair has been completed, clear the DTC and then check that the vehicle has returned to normal by performing the following All Readiness check procedure.

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• When clearing the permanent DTCs, refer to the "CLEAR PERMANENT DTC" procedure.

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1. Clear the DTCs (even if no DTCs are stored, perform the clear DTC procedure).
2. Turn the ignition switch off and wait for 2 minutes or more.
3. Turn the ignition switch to ON and wait for 5 seconds or more. [*1]
4. Turn the ignition switch to ON (READY) and wait for 5 seconds or more. [*2]

   HINT:

   Check that there are no abnormalities (abnormal sounds, coolant leaks, etc.).

5. Drive the vehicle for approximately 10 minutes mainly using the engine. [*3]

   NOTICE:

   As the state of charge of the HV battery may be low after driving in fail-safe mode, it will automatically be charged for 5 to 10 minutes with ignition switch ON (READY) after repairs have been performed.

   HINT:

   [*1] to [*3]: Normal judgment procedure.

   The normal judgment procedure is used to complete DTC judgment and also used when clearing permanent DTCs.

6. Enter the following menus: Powertrain / Motor Generator / Utility / All Readiness.
7. Check the DTC judgment result.

   HINT:

   • If the judgment result shows NORMAL, the system is normal.
   • If the judgment result shows ABNORMAL, the system has a malfunction.
   • If the judgment result shows INCOMPLETE, perform the normal judgment procedure again.

WIRING DIAGRAM

Refer to the wiring diagram for the Generator High-voltage Circuit.

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CAUTION / NOTICE / HINT

CAUTION:

Refer to the precautions before inspecting high voltage circuit.

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NOTICE:

• After the ignition switch is turned off, there may be a waiting time before disconnecting the negative (-) auxiliary battery terminal.

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• When disconnecting and reconnecting the auxiliary battery.

  HINT:

  When disconnecting and reconnecting the auxiliary battery, there is an automatic learning function that completes learning when the respective system is used.

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• DTC P0A7A73 is stored after DTC P0A7A9E and/or P1C5F19 is stored. After troubleshooting and repairing the malfunction which caused DTC P0A7A73 to be stored, be sure to troubleshoot the other DTCs.
• Depending on the conditions in which the vehicle is being operated when a short circuit occurs in the inverter with converter assembly, the hybrid vehicle transaxle assembly may be affected. As this DTC is stored if a short circuit occurs in the inverter with converter assembly, it is necessary to perform a road test to check the hybrid vehicle transaxle assembly. If problems are found, replace the malfunctioning parts.
• After completing the repair, including the repair of previously output DTCs, drive the vehicle at a speed of approximately 40 km/h (25 mph) for 1 minute and check that DTC P0A92000 is not output. If DTC P0A92000 is output, replace the hybrid vehicle transaxle assembly.

HINT:

• P0A7A73 may be output as a result of the malfunctions indicated by the DTCs in table below.
  1. The chart above is listed in inspection order of priority.
  2. Check DTCs that are output at the same time by following the listed order. (The main cause of the malfunction can be determined without performing unnecessary inspections.)

Malfunction Content	Relevant DTC
Insulation malfunction	P1C7C49	Hybrid/EV Battery Voltage System Isolation (A/C Area) Internal Electronic Failure
	P1C7D49	Hybrid/EV Battery Voltage System Isolation (Hybrid/EV Battery Area) Internal Electronic Failure
	P1C7E49	Hybrid/EV Battery Voltage System Isolation (Transaxle Area) Internal Electronic Failure
	P1C7F49	Hybrid/EV Battery Voltage System Isolation (Direct Current Area) Internal Electronic Failure
	P1C8049	Hybrid/EV Battery Voltage System Isolation (Rear Motor Area) Internal Electronic Failure

PROCEDURE

1.	CHECK HYBRID VEHICLE TRANSAXLE ASSEMBLY (GENERATOR (MG1))

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NG

GO TO STEP 3

OK

2.	REPLACE INVERTER WITH CONVERTER ASSEMBLY

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NEXT

GO TO STEP 12

3.	CHECK MOTOR CABLE (FOR MG1)

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NG

GO TO STEP 6

OK

4.	REPLACE HYBRID VEHICLE TRANSAXLE ASSEMBLY

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NEXT

5.	REPLACE INVERTER WITH CONVERTER ASSEMBLY

Click here

NEXT

GO TO STEP 12

6.	CHECK HYBRID VEHICLE TRANSAXLE ASSEMBLY (GENERATOR (MG1))

CAUTION:

Be sure to wear insulated gloves.

(a) Check that the service plug grip is not installed.

NOTICE:

After removing the service plug grip, do not turn the ignition switch to ON (READY), unless instructed by the repair manual because this may cause a malfunction.

(b) Disconnect the motor cable from the hybrid vehicle transaxle assembly.

(c) Check the generator (MG1) for an interphase short using a milliohmmeter. (1) Using a milliohmmeter, measure the resistance according to the value(s) in the table below. HINT: If the generator (MG1) temperature is high, the resistance will vary greatly from the specification. Therefore, measure the resistance at least 8 hours after the vehicle has been stopped. Standard Resistance: Tester Connection Condition Specified Condition Y2-4 (W) - Y2-5 (U) Ignition switch off 41.0 to 47.4 mΩ [*1] Y2-5 (U) - Y2-6 (V) Ignition switch off 41.1 to 47.5 mΩ [*2] Y2-4 (W) - Y2-6 (V) Ignition switch off 41.3 to 47.6 mΩ [*3] HINT: To correct the variation of the measured resistance due to temperature, use the following formula to calculate the resistance at 20°C (68°F). R20 = Rt / {1 + 0.00393 X (T - 20)} The calculation is based on the following: R20: Resistance at 20°C (68°F) (mΩ) Rt: Measured resistance (mΩ) T: Temperature when the resistance is measured (°C)

*a Motor Cable not connected (Hybrid Vehicle Transaxle Assembly)

(d) Check the difference in measured resistance values according to the table below.

Standard:

Inspection Item	Specified Condition
[*1] - [*2]	-1.1 to 0.9 mΩ
[*2] - [*3]	-1.2 to 0.8 mΩ
[*3] - [*1]	-0.7 to 1.3 mΩ

(e) Using a megohmmeter set to 500 V, measure the resistance according to the value(s) in the table below.

NOTICE:

Be sure to set the megohmmeter to 500 V when performing this test. Using a setting higher than 500 V can result in damage to the component being inspected.

Standard Resistance:

Tester Connection	Condition	Specified Condition
Y2-4 (W) - Body ground and shield ground	Ignition switch off	100 MΩ or higher
Y2-5 (U) - Body ground and shield ground	Ignition switch off	100 MΩ or higher
Y2-6 (V) - Body ground and shield ground	Ignition switch off	100 MΩ or higher

(f) Connect the motor cable.

NG

GO TO STEP 9

OK

7.	REPLACE MOTOR CABLE

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NEXT

8.	REPLACE INVERTER WITH CONVERTER ASSEMBLY

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NEXT

GO TO STEP 12

9.	REPLACE MOTOR CABLE

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NEXT

10.	REPLACE HYBRID VEHICLE TRANSAXLE ASSEMBLY

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NEXT

11.	REPLACE INVERTER WITH CONVERTER ASSEMBLY

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NEXT

12.	CHECK DTC OUTPUT (MOTOR GENERATOR)

(a) Check the other DTCs that were output together with DTC P0A7A73.

Powertrain > Motor Generator > Trouble Codes

Relevant DTC
P0A7A9E	Generator Inverter Stuck On
P1C5F19	Generator Inverter Circuit Current Above Threshold

NOTICE:

DTC P0A7A73 is stored after DTC P0A7A9E and/or P1C5F19 is stored. After troubleshooting and repairing the malfunction which caused DTC P0A7A73 to be stored, be sure to troubleshoot the other DTCs.

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