Last Modified: 05-13-2024 6.11:8.1.0 Doc ID: RM100000001N32X
Model Year Start: 2021 Model: Corolla Prod Date Range: [04/2020 - 09/2022]
Title: HYBRID / BATTERY CONTROL: MOTOR GENERATOR CONTROL SYSTEM (for LITHIUM-ION BATTERY with P610): P0A001C; Motor Electronics Coolant Temperature Sensor Circuit Voltage Out of Range; 2021 - 2022 MY Corolla Corolla HV [04/2020 - 09/2022]

DTC

P0A001C

Motor Electronics Coolant Temperature Sensor Circuit Voltage Out of Range

DTC SUMMARY

MALFUNCTION DESCRIPTION

These DTCs indicate that the temperature sensor value is abnormal. The cause of this malfunction may be one of the following:

Area

Main Malfunction Description

Step

Inverter low-voltage circuit

The connectors are not connected properly

2

Hybrid cooling system

Coolant circulation abnormal (frozen or leaking, etc.)

3

Inside of inverter

Inverter with converter assembly internal circuit malfunction

3

DESCRIPTION

The motor generator control ECU detects the HV coolant temperature using the HV coolant temperature sensor built into the inverter with converter assembly. The motor generator control ECU uses signals from the coolant temperature sensor to check the effectiveness of the inverter cooling system. If necessary, the motor generator control ECU will limit inverter output to help prevent inverter overheating. The motor generator control ECU also detects malfunctions in the sensor based on the HV coolant temperature sensor values.

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

MIL

Warning Indicate

P0A001C

Motor Electronics Coolant Temperature Sensor Circuit Voltage Out of Range

The actual inverter coolant temperature is high and the difference between the estimated inverter coolant temperature and the actual temperature exceeds a threshold for 10 seconds, or after a long soak, the inverter coolant temperature sensor value differs from the values of other sensors.

(1 trip detection logic)
  • Inverter cooling system
  • Cooling fan system
  • Inverter with converter assembly
  • Wire harness or connector

Comes on

Master Warning:

Comes on

Related Data List

DTC No.

Data List

P0A001C
  • Inverter Coolant Temperature
  • Ambient Temperature
  • Inverter Water Pump Duty Ratio
  • Inverter Water Pump Revolution
  • Motor Temperature
  • Generator Temperature

MONITOR DESCRIPTION

If the motor generator control ECU detects a malfunction of the Motor Electronics Coolant Temperature Sensor, it will illuminate the MIL and store a DTC.

MONITOR STRATEGY

Related DTCs

P0A01 (INF P0A001C): Motor Electronics Coolant Temperature Sensor Circuit Range / Performance

Required sensors/components

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

Motor generator control ECU

DTC P0A01 (INF P0A001C) 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 Corolla Corolla HV [04/2020 - 09/2022]; HYBRID / BATTERY CONTROL: MOTOR GENERATOR CONTROL SYSTEM (for LITHIUM-ION BATTERY with P610): UTILITY

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

    Click here 2021 - 2022 MY Corolla Corolla HV [04/2020 - 09/2022]; HYBRID / BATTERY CONTROL: MOTOR GENERATOR CONTROL SYSTEM (for LITHIUM-ION BATTERY with P610): 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 5 hours or more. [*1]

    NOTICE:

    Make sure that the temperature of the motor and generator do not drop below -10°C (14°F).

  5. Turn the power switch on (IG) and within 3 seconds or less, turn the power switch on (READY) and wait 10 seconds or more. [*2]

    HINT:

    It is possible to turn the power switch on (READY) without turning it on (IG) first.

  6. Turn the Techstream on. [*3]
  7. Drive the vehicle for approximately 10 minutes with the value of Data List item "Inverter Coolant Temperature" 25°C (77°F) or more. [*4]

    HINT:

    [*1] to [*4]: Normal judgment procedure.

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

  8. Enter the following menus: Powertrain / Motor Generator / Utility / All Readiness.
  9. 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 Cooling System.

Click here 2021 - 2022 MY Corolla Corolla HV [04/2020 - 09/2022]; HYBRID / BATTERY CONTROL: HYBRID CONTROL SYSTEM (for LITHIUM-ION BATTERY with P610): Cooling System+

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 - 2022 MY Corolla Corolla HV [04/2020 - 09/2022]; HYBRID / BATTERY CONTROL: MOTOR GENERATOR CONTROL SYSTEM (for LITHIUM-ION BATTERY with P610): 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 2021 - 2022 MY Corolla Corolla Hatchback Corolla HV GR Corolla [04/2020 - 09/2022]; INTRODUCTION: REPAIR INSTRUCTION: INITIALIZATION

PROCEDURE

1.

CHECK DTC OUTPUT (HYBRID CONTROL)

(a) Connect the Techstream to the DLC3.

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

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

(d) Check for DTCs.

Powertrain > Hybrid Control > Trouble Codes

Result

Proceed to

P0A001C only is output, or DTCs except the ones in the table below are also output.

A

Any of the following DTCs are also output.

B

Table 1

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

Table 2

Malfunction Content

Relevant DTC

Sensor and actuator circuit malfunction

P0C7396

Motor Electronics Coolant Pump "A" Component Internal Failure

P314A31

Motor Electronics Coolant Pump "A" No Signal

System malfunction

P0A9300

Inverter "A" Cooling System Performance

HINT:

  • P0A001C may be output as a result of the malfunctions 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)

A

2.

CHECK CONNECTOR CONNECTION CONDITION (INVERTER WITH CONVERTER ASSEMBLY CONNECTOR)

Click here 2021 - 2022 MY Corolla Corolla HV [04/2020 - 09/2022]; HYBRID / BATTERY CONTROL: MOTOR GENERATOR CONTROL SYSTEM (for LITHIUM-ION BATTERY with P610): P033500,P033531; Crankshaft Position Sensor "A"+

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

3.

CHECK COOLING SYSTEM

Click here 2021 - 2022 MY Corolla Corolla HV [04/2020 - 09/2022]; HYBRID / BATTERY CONTROL: HYBRID CONTROL SYSTEM (for LITHIUM-ION BATTERY with P610): Cooling System

HINT:

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

NEXT

REPLACE INVERTER WITH CONVERTER ASSEMBLY