Last Modified: 08-21-2023 6.11:8.1.0 Doc ID: RM100000001RHCJ
Model Year Start: 2021 Model: Avalon HV Prod Date Range: [08/2020 -           ]
Title: HYBRID / BATTERY CONTROL: HYBRID CONTROL SYSTEM (for LITHIUM-ION BATTERY): P1C8449; High Voltage Power Resource Circuit Short during Ready ON; 2021 - 2022 MY Avalon HV [08/2020 -        ]

DTC

P1C8449

High Voltage Power Resource Circuit Short during Ready ON

DTC SUMMARY

MALFUNCTION DESCRIPTION

The hybrid vehicle control ECU monitors the high-voltage wiring between the HV battery and inverter with converter assembly and detects an open circuit malfunction.

HINT:

  • This DTC is differentiated from P300449 based on detection timing (after power switch is turned on (READY)). If P300449 is also output at the same time, first perform troubleshooting for P300449.
  • If there is a SMRG stuck open malfunction, only P1C8449 is output.

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

Inverter voltage sensor (VH or VL) internal circuit malfunction

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

High voltage system malfunction

  • HV battery malfunction
  • HV battery junction block assembly malfunction
  • Inverter with converter assembly malfunction
  • High-voltage wire harness malfunction
  • High-voltage connector or connection 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 2021 - 2022 MY Avalon HV [08/2020 -        ]; HYBRID / BATTERY CONTROL: HYBRID CONTROL SYSTEM (for LITHIUM-ION BATTERY): P0AE411; Hybrid/EV Battery Precharge Contactor Circuit Short to Ground+

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

MIL

Warning Indicate

P1C8449

High Voltage Power Resource Circuit Short during Ready ON

High-voltage circuit malfunctions between the HV battery and inverter with converter assembly.

The voltage before boosting continues to be out of the HV battery voltage range or the integrated value of variation amount of the voltage before boosting for a specified period of time is large while the power switch is on (READY).

The EV electric battery fuse in the service plug grip is blown, the service plug grip is removed, SMRB or SMRG remains open, or the high-voltage cable has an open circuit.

(1 trip detection logic)

  • HV battery junction block assembly
  • Wire harness or connector
  • Hybrid vehicle control ECU
  • Battery ECU assembly

Comes on

Master Warning Light:

Comes on

Related Data List

DTC No.

Data List

P1C8449

  • Hybrid/EV Battery Voltage
  • Hybrid/EV Battery Current
  • VL-Voltage before Boosting
  • VH-Voltage after Boosting

The following items can be helpful when performing repairs:

Data List

  • Ready Signal

MONITOR DESCRIPTION

A malfunction is detected and the MIL is illuminated when the following condition is met:

A large fluctuation of DC/DC converter voltage is occurred due to power cable disconnection.

MONITOR STRATEGY

Related DTCs

P3004 (INF P1C8449): Power Cable Malfunction

Required sensors/components

DC/DC converter, HV battery

Frequency of operation

-

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

P3004 (INF P1C8449) 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 2021 - 2022 MY Avalon HV [08/2020 -        ]; HYBRID / BATTERY CONTROL: HYBRID CONTROL SYSTEM (for LITHIUM-ION BATTERY): UTILITY

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

    Click here 2021 - 2022 MY Avalon HV [08/2020 -        ]; HYBRID / BATTERY CONTROL: HYBRID CONTROL SYSTEM (for LITHIUM-ION BATTERY): DTC CHECK / CLEAR

  1. Connect the Techstream to the DLC3.
  2. Turn the power switch on (IG) and turn the Techstream on.
  3. Clear the DTCs (even if no DTCs are stored, perform the clear DTC procedure).
  4. Turn the power switch off and wait for 2 minutes or more.
  5. Turn the power switch on (IG) and turn the Techstream on.
  6. Turn the power switch on (READY) and wait for 3 minutes or more. [*1]

    HINT:

    • According to the display on the Techstream, read the Data List and monitor the values of "Hybrid/EV Battery Voltage" and "VL-Voltage before Boosting" for 3 minutes. If the difference between "Hybrid/EV Battery Voltage" and "VL-Voltage before Boosting" is always less than 50 V, the vehicle has returned to normal.
    • [*1] : Normal judgment procedure.

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

  7. Enter the following menus: Powertrain / Hybrid Control / Utility / All Readiness.
  8. 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 the HV battery high-voltage line circuit.

Click here 2021 - 2022 MY Avalon HV [08/2020 -        ]; HYBRID / BATTERY CONTROL: HYBRID CONTROL SYSTEM (for LITHIUM-ION BATTERY): HV Battery High-voltage Line Circuit+

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 2021 MY Avalon HV [08/2020 - 08/2021]; HYBRID / BATTERY CONTROL: HYBRID CONTROL SYSTEM (for LITHIUM-ION BATTERY): PRECAUTION 2022 MY Avalon HV [08/2021 -        ]; HYBRID / BATTERY CONTROL: HYBRID CONTROL SYSTEM (for LITHIUM-ION BATTERY): PRECAUTION

    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

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 2019 - 2022 MY Avalon Avalon HV [04/2018 -        ]; INTRODUCTION: REPAIR INSTRUCTION: PRECAUTION

PROCEDURE

1.

CHECK DTC OUTPUT (HYBRID CONTROL, MOTOR GENERATOR, HV BATTERY)

(a) Connect the Techstream to the DLC3.

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

(c) Enter the following menus: Powertrain / Hybrid Control, Motor Generator and HV Battery / Trouble Codes.

(d) Check for DTCs.

Powertrain > Hybrid Control > Trouble Codes

Powertrain > Motor Generator > Trouble Codes

Powertrain > HV Battery > Trouble Codes

Result

Proceed to

P1C8449 only is output, or P0A9563 and 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

DTCs of hybrid battery system in the tables below are output.

D

P0A9563 is also output.

E

Malfunction Content

System

Relevant DTC

Microcomputer malfunction

Hybrid control system

P0A1B49

Drive Motor "A" Control Module Internal Electronic Failure

P060647

Hybrid/EV Powertrain Control Module Processor Watchdog / Safety MCU Failure

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

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

Hybrid battery system

P060687

Hybrid/EV Battery Energy Control Module Processor to Monitoring Processor Missing Message

P060A47

Hybrid/EV Battery Energy Control Module Monitoring Processor Watchdog / Safety MCU Failure

P060A87

Hybrid/EV Battery Energy Control Module Processor from Monitoring Processor Missing Message

P060B16

Hybrid/EV Battery Energy Control Module A/D Processing Circuit Voltage Below Threshold

P060B49

Hybrid/EV Battery Energy Control Module A/D Processing Internal Electronic Failure

Power source circuit malfunction

Motor generator control system

P06D61C

Generator Control Module Offset Power Circuit Voltage Out of Range

Hybrid battery system

P1CBB12

Hybrid/EV Battery Current Sensor Power Supply Circuit Short to Auxiliary Battery

P1CBB14

Hybrid/EV Battery Current Sensor Power Supply Circuit Short to Ground or Open

Communication system malfunction

Hybrid control system

P312387

Lost Communication with Drive Motor Control Module "A" from Hybrid/EV Control Module Missing Message

U011187

Lost Communication with Hybrid/EV Battery Energy Control Module "A" Missing Message

Motor generator control system

P313387

Communication Error from Generator to Drive Motor "A" Missing Message

Sensor and actuator circuit malfunction

Hybrid control system

P0ABF00

Hybrid/EV Battery Current Sensor "A" Circuit Range/Performance

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

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

Hybrid battery system

P0ABF11

Hybrid/EV Battery Current Sensor "A" Circuit Short to Ground

P0ABF15

Hybrid/EV Battery Current Sensor "A" Circuit Short to Auxiliary Battery or Open

P0ABF28

Hybrid/EV Battery Current Sensor "A" Signal Bias Level Out of Range / Zero Adjustment Failure

P0ABF2A

Hybrid/EV Battery Current Sensor "A" Signal Stuck In Range

P0B0E11

Hybrid/EV Battery Current Sensor "B" Circuit Short to Ground

P0B0E15

Hybrid/EV Battery Current Sensor "B" Circuit Short to Auxiliary Battery or Open

P0B1362

Hybrid/EV Battery Current Sensor "A"/"B" Signal Compare Failure

System malfunction

Hybrid control system

P0A1F94

Hybrid/EV Battery Energy Control Module Unexpected Operation

P0D2D1C

Drive Motor "A" Inverter Voltage Sensor Voltage Out of Range

P0E311C

Boosting Converter Voltage Sensor "A" Voltage Out of Range

P1C8349

High Voltage Power Resource Circuit Voltage Sensor after Boosting Malfunction

P300449

High Voltage Power Resource Circuit Short during Pre-Charge

Motor generator control system

P1CB69E

Drive Motor "A" Inverter Voltage Sensor(VH) Stuck On

P0CA300

DC/DC Converter Step Up Voltage Performance

HINT:

  • P1C8449 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.

B

GO TO DTC CHART (HYBRID CONTROL SYSTEM) 2021 MY Avalon HV [08/2020 - 08/2021]; HYBRID / BATTERY CONTROL: HYBRID CONTROL SYSTEM (for LITHIUM-ION BATTERY): DIAGNOSTIC TROUBLE CODE CHART 2022 MY Avalon HV [08/2021 -        ]; HYBRID / BATTERY CONTROL: HYBRID CONTROL SYSTEM (for LITHIUM-ION BATTERY): DIAGNOSTIC TROUBLE CODE CHART

C

GO TO DTC CHART (MOTOR GENERATOR CONTROL SYSTEM) 2021 MY Avalon HV [08/2020 - 08/2021]; HYBRID / BATTERY CONTROL: MOTOR GENERATOR CONTROL SYSTEM (for LITHIUM-ION BATTERY): DIAGNOSTIC TROUBLE CODE CHART 2022 MY Avalon HV [08/2021 -        ]; HYBRID / BATTERY CONTROL: MOTOR GENERATOR CONTROL SYSTEM (for LITHIUM-ION BATTERY): DIAGNOSTIC TROUBLE CODE CHART

D

GO TO DTC CHART (HYBRID BATTERY SYSTEM)

E

GO TO DTC CHART (P0A9563)

A

2.

CLEAR DTC

Click here 2021 - 2022 MY Avalon HV [08/2020 -        ]; HYBRID / BATTERY CONTROL: HYBRID CONTROL SYSTEM (for LITHIUM-ION BATTERY): P06881F; ECM/PCM Power Relay Sense Circuit Intermittent+

NEXT

3.

CHECK DTC OUTPUT (HYBRID CONTROL, HV BATTERY)

(a) Connect the Techstream to the DLC3.

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

(c) Enter the following menus: Powertrain / Hybrid Control and HV Battery / Trouble Codes.

(d) Check for DTCs.

Powertrain > Hybrid Control > Trouble Codes

Powertrain > HV Battery > Trouble Codes

Result

Proceed to

P1C8449 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 hybrid battery system in the tables below are output.

C

Malfunction Content

System

Relevant DTC

System malfunction

Hybrid control system

P1AC413

Hybrid/EV Battery Stack 1 Current Interrupt Device Circuit Open

Hybrid battery system

P1AC413

Hybrid/EV Battery Stack 1 Current Interrupt Device Circuit Open

P1AC49E

Hybrid/EV Battery Stack 1 Current Interrupt Device Stuck On

P1AC513

Hybrid/EV Battery Stack 2 Current Interrupt Device Circuit Open

P1AC59E

Hybrid/EV Battery Stack 2 Current Interrupt Device Stuck On

HINT:

  • P1C8449 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.

B

GO TO DTC CHART (HYBRID CONTROL SYSTEM) 2021 MY Avalon HV [08/2020 - 08/2021]; HYBRID / BATTERY CONTROL: HYBRID CONTROL SYSTEM (for LITHIUM-ION BATTERY): DIAGNOSTIC TROUBLE CODE CHART 2022 MY Avalon HV [08/2021 -        ]; HYBRID / BATTERY CONTROL: HYBRID CONTROL SYSTEM (for LITHIUM-ION BATTERY): DIAGNOSTIC TROUBLE CODE CHART

C

GO TO DTC CHART (HYBRID BATTERY SYSTEM)

A

4.

CHECK DTC OUTPUT (HYBRID CONTROL)

(a) Connect the Techstream to the DLC3.

(b) With the vehicle stopped, apply the parking brake and turn the power switch on (READY).

HINT:

  • If the power switch could not be turned on (READY), turn the power switch off and check for DTCs after turning the power switch on (READY) again.
  • Because P300449 uses 2 trip detection logic, the DTC detection conditions need to be met 2 times.

(c) Ensure the safety of the areas in front and at the back of the vehicle.

(d) Move the shift lever to D and depress both the accelerator pedal and brake pedal at the same time.

HINT:

Depressing both the accelerator pedal and brake pedal at the same time causes the HV battery current to flow and ensures that there is no problem with the high-voltage wiring.

(e) Enter the following menus: Powertrain / Hybrid Control / Trouble Codes.

(f) Check for DTCs.

Powertrain > Hybrid Control > Trouble Codes

Result

Proceed to

P1C8449 is output, or no DTCs are output.

A

Power switch could not be turned on (READY) and DTC P300449 is output.

B

(g) Turn the power switch off.

B

GO TO DTC CHART (P300449)

A

5.

CHECK CONNECTOR CONNECTION CONDITION (HYBRID VEHICLE CONTROL ECU CONNECTOR)

Click here 2021 - 2022 MY Avalon HV [08/2020 -        ]; HYBRID / BATTERY CONTROL: HYBRID CONTROL SYSTEM (for LITHIUM-ION BATTERY): P056014; System Voltage (BATT) Circuit Short to Ground or Open+

NG

CONNECT SECURELY

OK

6.

CHECK CONNECTOR CONNECTION CONDITION (FLOOR WIRE CONNECTOR)

Click here 2021 - 2022 MY Avalon HV [08/2020 -        ]; HYBRID / BATTERY CONTROL: HYBRID CONTROL SYSTEM (for LITHIUM-ION BATTERY): P0AA000; Hybrid/EV Battery Positive Contactor Circuit Stuck Closed+

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

B

CONNECT SECURELY

C

REPAIR OR REPLACE HARNESS OR CONNECTOR

A

7.

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

Click here 2021 - 2022 MY Avalon HV [08/2020 -        ]; HYBRID / BATTERY CONTROL: HYBRID CONTROL SYSTEM (for LITHIUM-ION BATTERY): P0AA000; Hybrid/EV Battery Positive Contactor Circuit Stuck Closed+

NG

CONNECT SECURELY

OK

8.

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 2021 MY Avalon HV [08/2020 - 08/2021]; HYBRID / BATTERY CONTROL: HV BATTERY (for LITHIUM-ION BATTERY): REMOVAL+ 2022 MY Avalon HV [08/2021 -        ]; HYBRID / BATTERY CONTROL: HV BATTERY (for LITHIUM-ION BATTERY): REMOVAL+

(c) Disconnect the K18 HV battery junction block assembly connector.

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

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

G46-4 (SMRB) - K18-1 (SMRB)

Power switch off

Below 1 Ω

G46-1 (SMRG) - K18-4 (SMRG)

Power switch off

Below 1 Ω

*a

Rear view of wire harness connector

(to Hybrid Vehicle Control ECU)

*b

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.

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

OK

9.

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 2021 MY Avalon HV [08/2020 - 08/2021]; HYBRID / BATTERY CONTROL: HV BATTERY (for LITHIUM-ION BATTERY): REMOVAL+ 2022 MY Avalon HV [08/2021 -        ]; HYBRID / BATTERY CONTROL: HV BATTERY (for LITHIUM-ION BATTERY): REMOVAL+

(c) Disconnect the K18 HV battery junction block assembly connector.

(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.

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

OK

10.

CHECK HV BATTERY

CAUTION:

Be sure to wear insulated gloves and protective goggles.

(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 electric vehicle battery plug assembly.

Click here 2021 MY Avalon HV [08/2020 - 08/2021]; HYBRID / BATTERY CONTROL: BATTERY PLUG (for LITHIUM-ION BATTERY): REMOVAL+ 2022 MY Avalon HV [08/2021 -        ]; HYBRID / BATTERY CONTROL: BATTERY PLUG (for LITHIUM-ION BATTERY): REMOVAL+

(c) Disconnect the y10 and y13 HV battery high voltage connectors.

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

Standard Voltage:

Tester Connection

Condition

Specified Condition

y10-1 - y13-1 (-)

Power switch off

30 V or higher

*a

Front view of wire harness connector

(to No. 2 HV Battery Junction Block Assembly)

*b

Front view of wire harness connector

(to No. 1 HV Battery Junction Block Assembly)

(e) Reconnect the y10 and y13 HV battery high voltage connectors.

(f) Install the electric vehicle battery plug assembly.

NG

GO TO STEP 13

OK

11.

REPLACE HV BATTERY JUNCTION BLOCK ASSEMBLY

Click here 2021 MY Avalon HV [08/2020 - 08/2021]; HYBRID / BATTERY CONTROL: HV RELAY ASSEMBLY (for LITHIUM-ION BATTERY): REMOVAL 2022 MY Avalon HV [08/2021 -        ]; HYBRID / BATTERY CONTROL: HV RELAY ASSEMBLY (for LITHIUM-ION BATTERY): REMOVAL

NEXT

12.

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).

(c) Clear the DTCs.

Powertrain > Hybrid Control > Clear DTCs

(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/EV Battery Voltage, VL-Voltage before Boosting.

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

Powertrain > Hybrid Control > Data List

Tester Display

VL-Voltage before Boosting

Hybrid/EV Battery Voltage

Result

Proceed to

Difference between "Hybrid/EV Battery Voltage" and "VL-Voltage before Boosting" is always less than 50 V.

A

Difference between "Hybrid/EV Battery Voltage" and "VL-Voltage before Boosting" is 50 V or more.

B

(h) Turn the power switch off.

A

END

B

REPLACE HYBRID VEHICLE CONTROL ECU 2019 - 2021 MY Avalon HV [04/2018 - 08/2021]; HYBRID / BATTERY CONTROL: HYBRID VEHICLE CONTROL ECU: REMOVAL 2022 MY Avalon HV [08/2021 -        ]; HYBRID / BATTERY CONTROL: HYBRID VEHICLE CONTROL ECU: REMOVAL

13.

REPLACE BATTERY ECU ASSEMBLY

Click here 2021 MY Avalon HV [08/2020 - 08/2021]; HYBRID / BATTERY CONTROL: BATTERY ECU (for LITHIUM-ION BATTERY): REMOVAL 2022 MY Avalon HV [08/2021 -        ]; HYBRID / BATTERY CONTROL: BATTERY ECU (for LITHIUM-ION BATTERY): REMOVAL

NEXT

14.

SIMULATION TEST

(a) Connect the Techstream to the DLC3.

(b) Turn the power switch on (IG) and turn the Techstream on.

(c) Enter the following menus: Powertrain / Hybrid Control / Trouble Codes.

(d) Clear the DTCs and freeze frame data.

Powertrain > Hybrid Control > Clear DTCs

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

(f) Turn the power switch on (IG) and wait for 2 minutes or more.

(g) Enter the following menus: Powertrain / Hybrid Control and HV Battery / Trouble Codes.

(h) Check if DTCs are output.

Powertrain > Hybrid Control > Trouble Codes

Powertrain > HV Battery > Trouble Codes

Result

Proceed to

No DTCs are output.

A

DTCs of hybrid battery system are output.

B

(i) Turn the power switch off.

A

END

B

GO TO DTC CHART (HYBRID BATTERY SYSTEM)