Toyota Avalon (XX50): Inverter "A" Cooling System Performance (P0A9300). High Voltage Fuse Accumulated Load History (P0A9563). Hybrid/EV Battery Positive Contactor Circuit Stuck Closed (P0AA000)

Toyota Avalon (XX50) 2019-2022 Service & Repair Manual / Engine / Hybrid / Battery Control / Hybrid Control System / Inverter "A" Cooling System Performance (P0A9300). High Voltage Fuse Accumulated Load History (P0A9563). Hybrid/EV Battery Positive Contactor Circuit Stuck Closed (P0AA000)

Inverter "A" Cooling System Performance (P0A9300)

DTC SUMMARY

MALFUNCTION DESCRIPTION

This DTC indicates when the temperature sensor value inside the inverter has become abnormal. The cause of this malfunction may be one of the following:

Internal inverter malfunction

Inverter internal circuit malfunction
Malfunction in ECU that controls the inverter
Malfunction in sensor for inverter control (coolant temperature sensor)

Hybrid cooling system malfunction

Coolant is leaking, insufficient coolant level, frozen or the passenger of coolant is clogged.
Grille is blocked.

DESCRIPTION

Refer to the system description for the Cooling System.

Click here

DTC No.	Detection Item	DTC Detection Condition	Trouble Area	MIL	Warning Indicate
P0A9300	Inverter "A" Cooling System Performance	Inverter coolant temperature increases as well as the temperature of any inverter with converter assembly related parts due to an inverter cooling system malfunction. When the actual temperature of the inverter coolant is higher than the sensor value by a certain value or more and the actual temperature is high. (1 trip detection logic)	Inverter cooling system Inverter water pump assembly Inverter with converter assembly Cooling fan system Wire harness or connector	Comes on	Master Warning Light: Comes on

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

MIL

Warning Indicate

P0A9300

Inverter "A" Cooling System Performance

Inverter coolant temperature increases as well as the temperature of any inverter with converter assembly related parts due to an inverter cooling system malfunction.
When the actual temperature of the inverter coolant is higher than the sensor value by a certain value or more and the actual temperature is high.

(1 trip detection logic)

Inverter cooling system
Inverter water pump assembly
Inverter with converter assembly
Cooling fan system
Wire harness or connector

Comes on

Master Warning Light:

Comes on

Related Data List

DTC No.	Data List
P0A9300	Inverter Coolant Water Temperature Motor Inverter Temperature Generator Inverter Calculated Temperature Boosting Converter Temperature (Upper) Boosting Converter Temperature (Lower) Inverter Water Pump Revolution

MONITOR DESCRIPTION

If the hybrid vehicle control ECU detects a malfunction of the inverter cooling system, the ECU will illuminate the MIL and store a DTC.

MONITOR STRATEGY

Related DTCs	P0A93 (INF P0A9300): HV cooling system malfunction
Required sensors/components	Water pump, radiator fan, inverter, boost converter
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

Hybrid vehicle control ECU

DTC P0A93 (INF P0A9300) 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.
Click here
When clearing the permanent DTCs, refer to the "CLEAR PERMANENT DTC" procedure.
Click here

Connect the Techstream to the DLC3.
Turn the power switch on (IG) and turn the Techstream on.
Clear the DTCs (even if no DTCs are stored, perform the clear DTC procedure).
Turn the power switch off and wait for 2 minutes or more.
Turn the power switch on (IG) and turn the Techstream on.
With power switch on (IG) and wait for 5 seconds or more. [*1]
Turn the power switch on (READY) and wait for 5 seconds or more. [*2]
Perform a road test according to the freeze frame data item "Vehicle Speed" for approximately 10 minutes. [*3]
NOTICE:

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

HINT:

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

The normal judgment procedure is used to complete DTC judgment and also used when clearing permanent DTCs.
Enter the following menus: Powertrain / Hybrid Control / Utility / All Readiness.
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 or N/A, perform the normal judgment procedure again.

WIRING DIAGRAM

Refer to the wiring diagram for Cooling System.

Click here

CAUTION / NOTICE / HINT

CAUTION:

Before the following operations are conducted, take precautions to prevent electric shock by turning the power switch off, wearing insulated gloves, and removing the service plug grip from HV battery.
- Inspecting the high-voltage system
- Disconnecting the low voltage connector of the inverter with converter assembly
- Disconnecting the low voltage connector of the HV battery
To prevent electric shock, make sure to remove the service plug grip to cut off the high voltage circuit before servicing the vehicle.
After removing the service plug grip from the HV battery, put it in your pocket to prevent other technicians from accidentally reconnecting it while you are working on the high-voltage system.
After removing the service plug grip, wait for at least 10 minutes before touching any of the high-voltage connectors or terminals. After waiting for 10 minutes, check the voltage at the terminals in the inspection point in the inverter with converter assembly. The voltage should be 0 V before beginning work.

*a

Without waiting for 10 minutes

Click here

HINT:

Waiting for at least 10 minutes is required to discharge the high-voltage capacitor inside the inverter with converter assembly.

NOTICE:

After turning the power switch off, waiting time may be required before disconnecting the cable from the negative (-) auxiliary battery terminal. Therefore, make sure to read the disconnecting the cable from the negative (-) auxiliary battery terminal notices before proceeding with work.

Click here

PROCEDURE

1.	CHECK DTC OUTPUT

(a) Connect the Techstream to the DLC3.

(b) Turn the power switch on (IG).

(d) Check for DTCs.

Powertrain > Hybrid Control > Trouble Codes Powertrain > Motor Generator > Trouble Codes Powertrain > Engine > Trouble Codes

Result	Proceed to
P0A9300 only is output, or DTCs except the ones in the table below are also output.	A
DTCs of hybrid control system in the table below are output.	B
DTCs of motor generator control system in the table below are output.	C
DTCs of SFI system in the table below are output.	D

Table 1

Malfunction Content	System	Relevant DTC
Insulation malfunction	Hybrid control system	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

Table 2

Malfunction Content	System	Relevant DTC
Sensor and actuator circuit malfunction	Hybrid control system	P0C7396	Motor Electronics Coolant Pump "A" Component Internal Failure
	Hybrid control system	P314A31	Motor Electronics Coolant Pump "A" No Signal
	Motor generator control system	P0A0011	Motor Electronics Coolant Temperature Sensor Circuit Short to Ground
	Motor generator control system	P0A0015	Motor Electronics Coolant Temperature Sensor Circuit Short to Battery or Open
System malfunction	SFI system	P059F73	Active Grille Air Shutter "A" Actuator Stuck Closed
		P05A072	Active Grille Air Shutter "A" Actuator Stuck Open
		P05A074	Active Grille Air Shutter "A" Actuator Slipping
		P05A211	Active Grille Air Shutter "A" Circuit Short to Ground
		P05A212	Active Grille Air Shutter "A" Circuit Short to Battery
		P05A213	Active Grille Air Shutter "A" Circuit Open
		P05A27E	Active Grille Air Shutter "A" Actuator Stuck On
		P05A27F	Active Grille Air Shutter "A" Actuator Stuck Off
		P05B112	Active Grille Air Shutter "B" Circuit Short to Battery
		P05B114	Active Grille Air Shutter "B" Circuit Short to Ground or Open
		P05B131	Active Grille Air Shutter "B" No Signal
		U028487	Lost Communication with Active Grille Air Shutter Module "A" Missing Message

HINT:

P0A9300 may be output as a result of the malfunction indicated by the DTCs above.
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.)

(e) Turn the power switch off.

GO TO DTC CHART (HYBRID CONTROL SYSTEM)

GO TO DTC CHART (MOTOR GENERATOR CONTROL SYSTEM)

GO TO DTC CHART (SFI SYSTEM)

2.	CHECK CONNECTOR CONNECTION CONDITION (INVERTER WITH CONVERTER ASSEMBLY CONNECTOR)

Click here

Result	Proceed to
OK	A
NG (The connector is not connected securely.)	B
NG (The terminals are not making secure contact or are deformed, or water or foreign matter exists in the connector.)	C

CONNECT SECURELY

REPAIR OR REPLACE HARNESS OR CONNECTOR

3.	CHECK COOLING SYSTEM

Click here

HINT:

If the "Cooling System" inspection results are normal, perform the next step.

REPLACE HV COOLANT

High Voltage Fuse Accumulated Load History (P0A9563)

DESCRIPTION

The hybrid vehicle control ECU estimates the thermal load of the high voltage fuse. If the accumulated thermal load exceeds the threshold, the hybrid vehicle control ECU will store this DTC.

DTC No.	Detection Item	DTC Detection Condition	Trouble Area	MIL	Warning Indicate
P0A9563	High Voltage Fuse Accumulated Load History	Accumulated thermal load of the high voltage fuse estimated by the hybrid vehicle control ECU exceeds the threshold. (1 trip detection logic)	Hybrid battery terminal block	Does not come on	Master Warning Light: Does not come on

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

MIL

Warning Indicate

P0A9563

High Voltage Fuse Accumulated Load History

Accumulated thermal load of the high voltage fuse estimated by the hybrid vehicle control ECU exceeds the threshold.

(1 trip detection logic)

Hybrid battery terminal block

Does not come on

Master Warning Light:

Does not come on

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.

Click here

Connect the Techstream to the DLC3.
Turn the power switch on (IG) and turn the Techstream on.
Clear the DTCs (even if no DTCs are stored, perform the clear DTC procedure).
Turn the power switch off and wait for 2 minutes or more.
Turn the power switch on (IG) and turn the Techstream on.
With power switch on (IG) and wait for 5 seconds or more.
Enter the following menus: Powertrain / Hybrid Control / Utility / All Readiness.
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 or N/A, perform driving pattern again.

CAUTION / NOTICE / HINT

HINT:

If the hybrid battery terminal block has been replaced, make sure to perform "High Voltage Fuse Accumulated Load History Reset" and then clear the DTCs.

PROCEDURE

1.	REPLACE HYBRID BATTERY TERMINAL BLOCK

Click here

2.	PERFORM UTILITY (HIGH VOLTAGE FUSE ACCUMULATED LOAD HISTORY RESET)

Click here

3.	CLEAR DTC (HYBRID CONTROL)

(a) Connect the Techstream to the DLC3.

(b) Turn the power switch on (IG).

(d) Clear the DTCs and freeze frame data.

Powertrain > Hybrid Control > Clear DTCs

(e) Turn the power switch off.

END

Hybrid/EV Battery Positive Contactor Circuit Stuck Closed (P0AA000)

DTC SUMMARY

MALFUNCTION DESCRIPTION

The hybrid vehicle control ECU detects a stuck closed malfunction of a system main relay on the HV battery positive (+) terminal side.

The cause of this malfunction may be one of the following:

Inverter voltage sensor (VH) internal circuit malfunction

Voltage sensor (VH) malfunction
Motor generator control ECU (MG ECU) malfunction
Communication (wire harness) malfunction

High voltage system malfunction

HV battery junction block assembly malfunction

Low-voltage circuit (12 V) malfunction

Hybrid vehicle control ECU malfunction
HV battery junction block assembly malfunction
Low voltage wire harness malfunction
Low voltage connector malfunction

DESCRIPTION

Refer to the description for DTC P0AE411.

Click here

DTC No.	Detection Item	DTC Detection Condition	Trouble Area	MIL	Warning Indicate
P0AA000	Hybrid/EV Battery Positive Contactor Circuit Stuck Closed	Even the system main relay of HV battery positive (+) terminal side is turned off, the inverter voltage (VH) does not drop. (1 trip detection logic)	HV battery junction block assembly Inverter with converter assembly Hybrid vehicle control ECU Wire harness or connector	Does not come on	Master Warning Light: Comes on

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

MIL

Warning Indicate

P0AA000

Hybrid/EV Battery Positive Contactor Circuit Stuck Closed

Even the system main relay of HV battery positive (+) terminal side is turned off, the inverter voltage (VH) does not drop.

(1 trip detection logic)

HV battery junction block assembly
Inverter with converter assembly
Hybrid vehicle control ECU
Wire harness or connector

Does not come on

Master Warning Light:

Comes on

Related Data List

DTC No.	Data List
P0AA000	Hybrid Battery Voltage VH-Voltage after Boosting VL-Voltage before Boosting

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.

Click here

Connect the Techstream to the DLC3.
Turn the power switch on (IG) and turn the Techstream on.
Clear the DTCs (even if no DTCs are stored, perform the clear DTC procedure).
Turn the power switch off and wait for 2 minutes or more.
Turn the power switch on (IG) and turn the Techstream on.
Turn the power switch on (READY) and wait for 3 minutes or more.
HINT:

According to the display on the Techstream, read the Data List and monitor the values of "Hybrid Battery Voltage" and "VL-Voltage before Boosting" for 3 minutes. If the difference between "Hybrid Battery Voltage" and "VL-Voltage before Boosting" is always less than 100 V, the vehicle has returned to normal.
Enter the following menus: Powertrain / Hybrid Control / Utility / All Readiness.
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 or N/A, perform driving pattern again.

WIRING DIAGRAM

Refer to the wiring diagram for the HV battery high-voltage line circuit.

Click here

CAUTION / NOTICE / HINT

CAUTION:

Before the following operations are conducted, take precautions to prevent electric shock by turning the power switch off, wearing insulated gloves, and removing the service plug grip from HV battery.
- Inspecting the high-voltage system
- Disconnecting the low voltage connector of the inverter with converter assembly
- Disconnecting the low voltage connector of the HV battery
To prevent electric shock, make sure to remove the service plug grip to cut off the high voltage circuit before servicing the vehicle.
After removing the service plug grip from the HV battery, put it in your pocket to prevent other technicians from accidentally reconnecting it while you are working on the high-voltage system.
After removing the service plug grip, wait for at least 10 minutes before touching any of the high-voltage connectors or terminals. After waiting for 10 minutes, check the voltage at the terminals in the inspection point in the inverter with converter assembly. The voltage should be 0 V before beginning work.
Click here

HINT:

Waiting for at least 10 minutes is required to discharge the high-voltage capacitor inside the inverter with converter assembly.

*a

Without waiting for 10 minutes
Make sure to insulate the high-voltage connectors and terminals of the HV battery with insulating tape after removing it.
If the HV battery stored without insulating the connectors and terminals, electric shock or fire may result.

NOTICE:

After turning the power switch off, waiting time may be required before disconnecting the cable from the negative (-) auxiliary battery terminal. Therefore, make sure to read the disconnecting the cable from the negative (-) auxiliary battery terminal notices before proceeding with work.
Click here
If the DTCs are cleared or the cable is disconnected and reconnected to the negative (-) auxiliary battery terminal before performing repairs, turning the power switch on (READY) may cause a malfunction. Do not turn the power switch on (READY).

HINT:

If DTC P0AA000 is output, the power switch cannot be turned on (READY).

PROCEDURE

1.	CHECK DTC OUTPUT (HYBRID CONTROL, MOTOR GENERATOR)

(a) Connect the Techstream to the DLC3.

(b) Turn the power switch on (IG).

(d) Check for DTCs.

Powertrain > Hybrid Control > Trouble Codes Powertrain > Motor Generator > Trouble Codes

Result	Proceed to
P0AA000 only is output, or DTCs except the ones in the table below are also output.	A
DTCs of hybrid control system in the tables below are output.	B
DTCs of motor generator control system in the tables below are output.	C

Malfunction Content	System	Relevant DTC
Microcomputer malfunction	Hybrid control system	P060647	Hybrid/EV Powertrain Control Module Processor Watchdog / Safety MCU Failure
		P060687	Hybrid/EV Powertrain Control Module Processor to Monitoring Processor Missing Message
		P060A47	Hybrid/EV Powertrain Control Module Monitoring Processor Watchdog / Safety MCU Failure
		P060A87	Hybrid/EV Powertrain Control Module Processor from Monitoring Processor Missing Message
		P0A1B49	Drive Motor "A" Control Module Internal Electronic Failure
		P1C9E9F	Hybrid/EV System Reset Stuck Off
	Motor generator control system	P0A1B1F	Generator Control Module Circuit Intermittent
		P0A1A47	Generator Control Module Watchdog / Safety μC Failure
		P0A1A49	Generator Control Module Internal Electronic Failure
		P1C2A1C	Generator A/D Converter Circuit Circuit Voltage Out of Range
		P1C2A49	Generator A/D Converter Circuit Internal Electronic Failure
		P1C2B1C	Drive Motor "A" Control Module A/D Converter Circuit Voltage Out of Range
		P1C2B49	Drive Motor "A" Control Module A/D Converter Circuit Internal Electronic Failure
		P1CAC49	Generator Position Sensor Internal Electronic Failure
		P1CAD49	Drive Motor "A" Position Sensor Internal Electronic Failure
		P1CAF38	Generator Position Sensor REF Signal Cycle Malfunction Signal Frequency Incorrect
		P1CB038	Drive Motor "A" Position Sensor REF Signal Frequency Incorrect
		P313383	Communication Error from Generator to Drive Motor "A" Value of Signal Protection Calculation Incorrect
		P313386	Communication Error from Generator to Drive Motor "A" Signal Invalid
		P313387	Communication Error from Generator to Drive Motor "A" Missing Message
Power source circuit malfunction	Motor generator control system	P06D61C	Generator Control Module Offset Power Circuit Voltage Out of Range
Power source circuit malfunction	Motor generator control system	P06B01C	Generator Control Module Position Sensor REF Power Source Circuit Voltage Out of Range
Communication system malfunction	Hybrid control system	P312387	Lost Communication with Drive Motor Control Module "A" from Hybrid/EV Control Module Missing Message
Sensor and actuator circuit malfunction	Hybrid control system	P0AD911	Hybrid/EV Battery Positive Contactor Circuit Short to Ground
		P0AD915	Hybrid/EV Battery Positive Contactor Circuit Short to Auxiliary Battery or Open
		P0ADD11	Hybrid/EV Battery Negative Contactor Circuit Short to Ground
		P0ADD15	Hybrid/EV Battery Negative Contactor Circuit Short to Auxiliary Battery or Open
		P0AE411	Hybrid/EV Battery Precharge Contactor Circuit Short to Ground
		P0AE415	Hybrid/EV Battery Precharge Contactor Circuit Short to Auxiliary Battery or Open
	Motor generator control system	P0A3F16	Drive Motor "A" Position Sensor Circuit Voltage Below Threshold
		P0A4B16	Generator Position Sensor Circuit Voltage Below Threshold
		P0A4B21	Generator Position Sensor Signal Amplitude < Minimum
		P0A4B22	Generator Position Sensor Signal Amplitude > Maximum
		P0C5013	Drive Motor "A" Position Sensor Circuit "A" Circuit Open
		P0C5016	Drive Motor "A" Position Sensor Circuit "A" Circuit Voltage Below Threshold
		P0C5017	Drive Motor "A" Position Sensor Circuit "A" Circuit Voltage Above Threshold
		P0C5A13	Drive Motor "A" Position Sensor Circuit "B" Circuit Open
		P0C5A16	Drive Motor "A" Position Sensor Circuit "B" Circuit Voltage Below Threshold
		P0C5A17	Drive Motor "A" Position Sensor Circuit "B" Circuit Voltage Above Threshold
		P0C6413	Generator Position Sensor Circuit "A" Circuit Open
		P0C6416	Generator Position Sensor Circuit "A" Circuit Voltage Below Threshold
		P0C6417	Generator Position Sensor Circuit "A" Circuit Voltage Above Threshold
		P0C6913	Generator Position Sensor Circuit "B" Circuit Open
		P0C6916	Generator Position Sensor Circuit "B" Circuit Voltage Below Threshold
		P0C6917	Generator Position Sensor Circuit "B" Circuit Voltage Above Threshold
System malfunction	Hybrid control system	P0D2D1C	Drive Motor "A" Inverter Voltage Sensor Voltage Out of Range
		P1C8349	High Voltage Power Resource Circuit Voltage Sensor after Boosting Malfunction
		P0C7600	Hybrid/EV Battery System Discharge Time Too Long
	Motor generator control system	P0D2D16	Drive Motor "A" Inverter Voltage Sensor (VH) Circuit Voltage Below Threshold
		P0D2D17	Drive Motor "A" Inverter Voltage Sensor (VH) Circuit Voltage Above Threshold
		P1CB69E	Drive Motor "A" Inverter Voltage Sensor (VH) Stuck On

HINT:

P0AA000 may be output as a result of the malfunction indicated by the DTCs above.
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.)

(e) Turn the power switch off.

GO TO DTC CHART (HYBRID CONTROL SYSTEM)

GO TO DTC CHART (MOTOR GENERATOR CONTROL SYSTEM)

2.	CHECK FREEZE FRAME DATA (HYBRID CONTROL)

(a) Connect the Techstream to the DLC3.

(b) Turn the power switch on (IG).

(d) Read the freeze frame data of DTC P0AA000.

Powertrain > Hybrid Control > Trouble Codes

NOTICE:

As freeze frame data is stored immediately before and after a DTC is stored, make sure to only read the values for the moment the DTC was stored ("0(s)").

Result	Proceed to
Difference between "VL-Voltage before Boosting" and "VH-Voltage after Boosting" is less than 76 V.	A
Difference between "VL-Voltage before Boosting" and "VH-Voltage after Boosting" is 76 V or more.	B

HINT:

If VH-Voltage after Boosting is output even when an off command is being sent to the system main relay (positive side), P0AA000 is output. If the difference between the "VL-Voltage before Boosting" and the "VH-Voltage after Boosting" is large, it is determined that there is an inverter (VH sensor) malfunction.

(e) Turn the power switch off.

REPLACE INVERTER WITH CONVERTER ASSEMBLY

3.	CHECK CONNECTOR CONNECTION CONDITION (HYBRID VEHICLE CONTROL ECU CONNECTOR)

Click here

GO TO STEP 5

4.	CONNECT SECURELY

5.	CHECK CONNECTOR CONNECTION CONDITION (FLOOR WIRE CONNECTOR)

(a) Check the connection condition of the KG8 floor wire connector and the contact pressure of each terminal. Check the terminals for deformation, and check the connector for water ingress and foreign matter.

Click here

OK:

- The connector is connected securely.

- The terminals are not deformed and are connected securely.

- No water or foreign matter in the connector.

Result	Proceed to
OK	A
NG (The connector is not connected securely.)	B
NG (The terminals are not making secure contact or are deformed, or water or foreign matter exists in the connector.)	C

GO TO STEP 8

GO TO STEP 7

6.	CONNECT SECURELY

GO TO STEP 8

7.	REPAIR OR REPLACE HARNESS OR CONNECTOR

8.	CHECK CONNECTOR CONNECTION CONDITION (HV BATTERY JUNCTION BLOCK ASSEMBLY CONNECTOR)

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 power switch on (READY), unless instructed by the repair manual because this may cause a malfunction.

(b) Remove the No. 1 HV battery cover panel RH.

Click here

(c) Check the connector connections and contact pressure of the relevant terminals of the K18 HV battery junction block assembly connector.

Click here

OK:

The connectors are connected securely and there are no contact pressure problems.

(d) Install the No. 1 HV battery cover panel RH.

GO TO STEP 10

9.	CONNECT SECURELY

10.	CHECK GROUND WIRE CONNECTION CONDITION (SMR ACTIVATION LOW-VOLTAGE CIRCUIT)

(a) Check the installation condition of the ground wire KA.

OK:

The ground wire KA is securely installed.

GO TO STEP 12

11.	CONNECT SECURELY

12.	CHECK HARNESS AND CONNECTOR (HYBRID VEHICLE CONTROL ECU - HV BATTERY JUNCTION BLOCK ASSEMBLY)

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 power switch on (READY), unless instructed by the repair manual because this may cause a malfunction.

(b) Remove the No. 1 HV battery cover panel RH.

Click here

(d) Disconnect the G46 hybrid vehicle control ECU connector.

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

Standard Resistance (Check for Open):

Tester Connection	Condition	Specified Condition
G46-4 (SMRB) - K18-1 (SMRB)	Power switch off	Below 1 Ω

Standard Resistance (Check for Short):

Tester Connection	Condition	Specified Condition
G46-4 (SMRB) or K18-1 (SMRB) - Body ground and other terminals	Power switch off	10 kΩ or higher

Rear view of wire harness connector

(to Hybrid Vehicle Control ECU)

Front view of wire harness connector

(to HV Battery Junction Block Assembly)

(f) Reconnect the G46 hybrid vehicle control ECU connector.

(g) Reconnect the K18 HV battery junction block assembly connector.

(h) Install the No. 1 HV battery cover panel RH.

GO TO STEP 14

13.	REPAIR OR REPLACE HARNESS OR CONNECTOR

14.	CHECK HARNESS AND CONNECTOR (HV BATTERY JUNCTION BLOCK ASSEMBLY - BODY GROUND)

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 power switch on (READY), unless instructed by the repair manual because this may cause a malfunction.

(b) Remove the No. 1 HV battery cover panel RH.

Click here

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

Standard Resistance:

Tester Connection	Condition	Specified Condition
K18-3 (GND) - Body ground	Power switch off	Below 1 Ω

*a	Front view of wire harness connector (to HV Battery Junction Block Assembly)

(e) Reconnect the K18 HV battery junction block assembly connector.

(f) Install the No. 1 HV battery cover panel RH.

GO TO STEP 16

15.	REPAIR OR REPLACE HARNESS OR CONNECTOR

16.	INSPECT HV BATTERY JUNCTION BLOCK ASSEMBLY (SMRB)

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 power switch on (READY), unless instructed by the repair manual because this may cause a malfunction.

(b) Remove the No. 1 HV battery cover panel RH.

Click here

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

Component without harness connected

(HV Battery Junction Block Assembly)

Standard Resistance:

Tester Connection	Condition	Specified Condition
K18-1 (SMRB) - K18-3 (GND)	-40 to 80°C (-40 to 176°F)	25.0 to 59.0 Ω

(e) Reconnect the K18 HV battery junction block assembly connector.

(f) Install the No. 1 HV battery cover panel RH.

GO TO STEP 19

17.	CHECK HV BATTERY JUNCTION BLOCK ASSEMBLY (SMRB)

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 power switch on (READY), unless instructed by the repair manual because this may cause a malfunction.

(b) Remove the No. 1 HV battery cover panel RH.

Click here

(d) Disconnect the 2 HV battery high voltage connectors from the HV battery junction block assembly.

NOTICE:

Insulate each disconnected high-voltage connector with insulating tape. Wrap the connector from the wire harness side to the end of the connector.

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

Standard Resistance:

Tester Connection	Condition	Specified Condition
S2-1 (CBI) - y5-1 (+)	Power switch off	10 kΩ or higher

HINT:

If a system main relay is stuck closed, inspect the HV battery junction block assembly without removing it from the vehicle, in order to keep the relay closed.
If the result of reading the freeze frame data is A, the HV battery junction block assembly must be replaced. Measuring resistance can determine that this is either a present or past malfunction.

*a	Component without harness connected (HV Battery Junction Block Assembly)

(f) Reconnect the 2 HV battery high voltage connectors.

(g) Reconnect the 2 HV floor under wire connectors.

(h) Install the No. 1 HV battery cover panel RH.

Result	Judgment	Proceed to
OK	Past malfunction	A
NG	Present malfunction	B

GO TO STEP 20

18.	REPLACE HV BATTERY JUNCTION BLOCK ASSEMBLY

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GO TO STEP 21

19.	REPLACE HV BATTERY JUNCTION BLOCK ASSEMBLY

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GO TO STEP 21

20.	REPLACE HV BATTERY JUNCTION BLOCK ASSEMBLY

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21.	CHECK HYBRID VEHICLE CONTROL ECU (CHECK FOR NORMAL OPERATION)

CAUTION:

Be sure to wear insulated gloves.

(a) Install the service plug grip.

(b) Turn the power switch on (IG).

Click here

(d) Turn the power switch off and wait for 2 minutes or more.

(e) Turn the power switch on (READY).

(f) Enter the following menus: Powertrain / Hybrid Control / Data List / Hybrid Battery Voltage, VL-Voltage before Boosting.

(g) According to the display on the Techstream, read the Data List and monitor the values of "Hybrid Battery Voltage" and "VL-Voltage before Boosting" for 3 minutes.

Powertrain > Hybrid Control > Data List

Tester Display
VL-Voltage before Boosting
Hybrid Battery Voltage

Result	Proceed to
Difference between "Hybrid Battery Voltage" and "VL-Voltage before Boosting" is always less than 100 V.	A
Difference between "Hybrid Battery Voltage" and "VL-Voltage before Boosting" is 100 V or more.	B

(h) Turn the power switch off.

END

REPLACE HYBRID VEHICLE CONTROL ECU AND HV BATTERY JUNCTION BLOCK ASSEMBLY

Hybrid/EV Battery Cooling Fan 1 Component Internal Failure (P0A8196,P0A8198)

Hybrid/EV Battery Positive and Negative Contactor Actuator Stuck Closed (P0AA073)

See More:

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