Last Modified: 05-13-2024 6.11:8.1.0 Doc ID: RM1000000026PZ5
Model Year Start: 2023 Model: Corolla HV Prod Date Range: [09/2022 -           ]
Title: HYBRID / BATTERY CONTROL: HYBRID BATTERY SYSTEM (for LITHIUM-ION BATTERY with PA10): P1A001C,P301A1C; Hybrid Battery Stack 2 Cell Voltage Detection Voltage Out of Range; 2023 - 2025 MY Corolla HV [09/2022 -        ]

DTC

P1A001C

Hybrid Battery Stack 2 Cell Voltage Detection Voltage Out of Range

DTC

P301A1C

Hybrid Battery Stack 1 Cell Voltage Detection Voltage Out of Range

DESCRIPTION

The HV battery is composed of 56 cells (3.7 V each) in series. The battery ECU assembly monitors the voltage of each HV battery cell to detect malfunctions of the HV battery.

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

MIL

Warning Indicate

Note

P1A001C

Hybrid Battery Stack 2 Cell Voltage Detection Voltage Out of Range

An open is detected in the HV battery cell voltage detection circuits of the No. 2 HV supply stack sub-assembly.

(1 trip detection logic)
  • HV battery
  • Battery ECU assembly

Comes on

Master Warning:

Comes on

SAE Code: P1A00

P301A1C

Hybrid Battery Stack 1 Cell Voltage Detection Voltage Out of Range

An open is detected in the HV battery cell voltage detection circuits of the No. 1 HV supply stack sub-assembly.

(1 trip detection logic)
  • HV battery
  • Battery ECU assembly

Comes on

Master Warning:

Comes on

SAE Code: P301A

MONITOR DESCRIPTION

If the voltage of an HV battery cell is abnormal, the battery ECU assembly will determine that a malfunction has occurred. When the malfunction detection condition is satisfied, the battery ECU assembly will illuminate the MIL and store a DTC.

MONITOR STRATEGY

Related DTCs

P1A00 (INF P1A001C), P301A (INF P301A1C): Battery voltage detection circuits malfunction

Required sensors/components

Battery ECU assembly

Frequency of operation

Continuous

Duration

TMC's intellectual property

MIL operation

Immediately

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

Battery ECU assembly

DTC P1A00 (INF P1A001C) is not detected

DTC P301A (INF P301A1C) 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 2023 - 2025 MY Corolla HV [09/2022 -        ]; HYBRID / BATTERY CONTROL: HYBRID BATTERY SYSTEM (for LITHIUM-ION BATTERY with PA10): UTILITY

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

    Click here 2023 - 2025 MY Corolla HV [09/2022 -        ]; HYBRID / BATTERY CONTROL: HYBRID BATTERY SYSTEM (for LITHIUM-ION BATTERY with PA10): DTC CHECK / CLEAR

  1. Connect the GTS to the DLC3.
  2. Turn the ignition switch to ON and turn the GTS on.
  3. Clear the DTCs (even if no DTCs are stored, perform the clear DTC procedure).
  4. Turn the ignition switch off and wait for 2 minutes or more.
  5. Turn the ignition switch to ON and turn the GTS on.
  6. With ignition switch ON and wait for 10 seconds or more.[*1]

    HINT:

    [*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 / HV Battery / 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, perform the normal judgment procedure again.

WIRING DIAGRAM

CAUTION / NOTICE / HINT

CAUTION:

Refer to the precautions before inspecting high voltage circuit.

Click here 2023 - 2025 MY Corolla HV [09/2022 -        ]; HYBRID / BATTERY CONTROL: HYBRID BATTERY SYSTEM (for LITHIUM-ION BATTERY with PA10): PRECAUTION

NOTICE:

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

    Click here 2023 - 2025 MY Corolla Corolla Hatchback Corolla HV GR Corolla [09/2022 -        ]; SETUP: WHEN DISCONNECTING OR RECONNECTING BATTERY TERMINAL: BEFORE DISCONNECTING BATTERY

  • 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.

    Click here 2023 MY Corolla Corolla Hatchback Corolla HV GR Corolla [09/2022 - 11/2022]; SETUP: WHEN DISCONNECTING OR RECONNECTING BATTERY TERMINAL: AUTOMATIC LEARNING CHART 2023 - 2025 MY Corolla Corolla Hatchback Corolla HV GR Corolla [11/2022 -        ]; SETUP: WHEN DISCONNECTING OR RECONNECTING BATTERY TERMINAL: AUTOMATIC LEARNING CHART

PROCEDURE

1.

CHECK DTC OUTPUT (HV BATTERY, HYBRID CONTROL)

(a) Check for DTCs.

Powertrain > HV Battery > Trouble Codes

Powertrain > Hybrid Control > Trouble Codes

Result

Proceed to

"P1A001C or P301A1C" only is output, or DTCs except the ones in the table below are also output.

A

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

B

DTCs of hybrid control system in the table below are output.

C

System

Relevant DTC

Hybrid battery system

P060A47

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

P060B49

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

P060687

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

Hybrid control system

P0A1F94

Hybrid/EV Battery Energy Control Module Unexpected Operation

(b) Turn the ignition switch off.

B

GO TO DTC CHART (HYBRID BATTERY SYSTEM)
C

GO TO DTC CHART (HYBRID CONTROL SYSTEM)

A

2.

CHECK DTC

(a) Check the DTCs that were output when the vehicle was brought to the workshop.

Result

Proceed to

"P1A001C" is also output.

A

"P301A1C" is also output.

B
B

GO TO STEP 6

A

3.

CHECK CONNECTOR CONNECTION CONDITION (BATTERY ECU ASSEMBLY CONNECTOR)

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 ignition switch to ON (READY), unless instructed by the repair manual because this may cause a malfunction.

(b) Check the connector connections and contact pressure of the relevant terminals for the battery ECU assembly.

Click here 2019 - 2025 MY Corolla Corolla Hatchback Corolla HV GR Corolla [06/2018 -        ]; INTRODUCTION: HOW TO TROUBLESHOOT ECU CONTROLLED SYSTEMS: ELECTRONIC CIRCUIT INSPECTION PROCEDURE

OK:

The connector is connected securely and there are no contact problems.

Result:

Result

Proceed to

OK

A

Not connected securely

The terminals are not damaged or corroded

B

Not connected securely

The terminals are damaged or corroded

C
B

CONNECT SECURELY
C

REPLACE HV BATTERY

A

4.

CHECK FREEZE FRAME DATA (HYBRID/EV BATTERY CELL VOLTAGE)

(a) Read the value of freeze frame data items "Hybrid/EV Battery Cell 29 Voltage" through "Hybrid/EV Battery Cell 56 Voltage" for DTC P1A001C and make a note if the value of any is 1.6 V or less.

Powertrain > HV Battery > Trouble Codes

(b) Turn the ignition switch off.

NEXT

5.

CHECK HV BATTERY (HV BATTERY CELL VOLTAGE 29 - 56)

Click here 2023 - 2025 MY Corolla HV [09/2022 -        ]; HYBRID / BATTERY CONTROL: HYBRID BATTERY SYSTEM (for LITHIUM-ION BATTERY with PA10): P0E2D00; Hybrid/EV Battery Energy Control Module Hybrid/EV Battery Monitor Performance+

Result

Proceed to

The voltage between the terminals is 1.6 V or less.

A

Other than above

B
A

REPLACE HV BATTERY

B

REPLACE BATTERY ECU ASSEMBLY

6.

CHECK CONNECTOR CONNECTION CONDITION (BATTERY ECU ASSEMBLY CONNECTOR)

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 ignition switch to ON (READY), unless instructed by the repair manual because this may cause a malfunction.

(b) Check the connector connections and contact pressure of the relevant terminals for the battery ECU assembly.

Click here 2019 - 2025 MY Corolla Corolla Hatchback Corolla HV GR Corolla [06/2018 -        ]; INTRODUCTION: HOW TO TROUBLESHOOT ECU CONTROLLED SYSTEMS: ELECTRONIC CIRCUIT INSPECTION PROCEDURE

OK:

The connector is connected securely and there are no contact problems.

Result:

Result

Proceed to

OK

A

Not connected securely

The terminals are not damaged or corroded

B

Not connected securely

The terminals are damaged or corroded

C
B

CONNECT SECURELY
C

REPLACE HV BATTERY

A

7.

CHECK FREEZE FRAME DATA (HYBRID/EV BATTERY CELL VOLTAGE)

(a) Read the value of freeze frame data items "Hybrid/EV Battery Cell 1 Voltage" through "Hybrid/EV Battery Cell 28 Voltage" for DTC P301A1C and make a note if the value of any is 1.6 V or less.

Powertrain > HV Battery > Trouble Codes

(b) Turn the ignition switch off.

NEXT

8.

CHECK HV BATTERY (HV BATTERY CELL VOLTAGE 1 - 28)

Click here 2023 - 2025 MY Corolla HV [09/2022 -        ]; HYBRID / BATTERY CONTROL: HYBRID BATTERY SYSTEM (for LITHIUM-ION BATTERY with PA10): P0E2D00; Hybrid/EV Battery Energy Control Module Hybrid/EV Battery Monitor Performance+

Result

Proceed to

The voltage between the terminals is 1.6 V or less.

A

Other than above

B
A

REPLACE HV BATTERY

B

REPLACE BATTERY ECU ASSEMBLY