Last Modified: 07-31-2024 6.11:8.1.0 Doc ID: RM100000001N40L
Model Year Start: 2021 Model: Corolla Prod Date Range: [04/2020 - 09/2022]
Title: HYBRID / BATTERY CONTROL: HYBRID CONTROL SYSTEM (for LITHIUM-ION BATTERY with P610): Generator High-voltage Circuit; 2021 - 2022 MY Corolla Corolla HV [04/2020 - 09/2022]

Generator High-voltage Circuit

DESCRIPTION

The cause of this malfunction may be the generator high-voltage circuit.

Check the generator internal resistance and the connection condition of the high-voltage line between the inverter and generator to check whether there is an open or short circuit.

Related Parts Check

Area

Inspection

Motor cable (for MG1) connection check

Check for the connection condition of the cable from the inverter to the generator.

Generator or motor cable (for MG1)

Check the generator (including cable) internal resistance and the insulation resistance with body ground to check for an open or short circuit.

WIRING DIAGRAM

CAUTION / NOTICE / HINT

This diagnostic procedure is referenced to in the diagnostic procedure of several DTCs.

If the result of this diagnostic procedure is normal, proceed as directed in the procedure for the DTC.

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: HYBRID 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 INVERTER WITH CONVERTER ASSEMBLY (MOTOR CABLE CONNECTION CONDITION)

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 inverter cover from the inverter with converter assembly.

(c) Check that the bolts for the motor cable are tightened to the specified torque, the generator cable is connected securely, and there are no contact problems.

Specified Condition:

T = 8.0 N*m (82 kgf*cm, 71 in.*lbf)

(d) Disconnect the motor cable from the inverter with converter assembly.

(e) Check for arc marks at the terminals for the motor cable.

Result

Proceed to

The terminals are connected securely and there are no contact problems.

There are no arc marks.

A

The terminals are not connected securely and there is a contact problem.

There are arc marks.

B

The terminals are not connected securely and there is a contact problem.

There are no arc marks.

C

The terminals are connected securely and there are no contact problems.

There are arc marks.

B

(f) Reconnect the motor cable.

(g) Reinstall the inverter cover.

B

REPLACE MALFUNCTIONING PARTS
C

CONNECT SECURELY
A

2.

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

(b) Remove the inverter cover from the inverter with converter assembly.

(c) Disconnect the motor cable from the inverter with converter assembly.

(d) 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 is stopped.

Standard Resistance:

Tester Connection

Condition

Specified Condition

p2-4 (W) - p2-5 (U)

Power switch off

106.1 to 117.0 mΩ

p2-5 (U) - p2-6 (V)

Power switch off

106.1 to 117.0 mΩ

p2-6 (V) - p2-4 (W)

Power switch off

106.1 to 117.0 mΩ

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)

*1

Shield Ground

*a

Motor Cable (for MG1)

(Inverter with Converter Assembly Side)

(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

p2-4 (W) - Body ground and shield ground

Power switch off

100 MΩ or higher

p2-5 (U) - Body ground and shield ground

Power switch off

100 MΩ or higher

p2-6 (V) - Body ground and shield ground

Power switch off

100 MΩ or higher

(f) Reconnect the motor cable.

(g) Reinstall the inverter cover.

OK

GENERATOR HIGH-VOLTAGE CIRCUIT NORMAL (PERFORM NEXT STEP FOR REFERENCED DTC)
NG

3.

CHECK HYBRID VEHICLE TRANSAXLE ASSEMBLY (MOTOR CABLE CONNECTION CONDITION)

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 inverter with converter assembly.

(c) Check that the bolts for the motor cable are tightened to the specified torque, the motor cable is connected securely, and there are no contact problems.

Specified Condition:

T=10 N*m (102 kgf*cm, 7 ft.*lbf)

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

(e) Check for arc marks at the terminals for the generator cable.

Result

Proceed to

The terminals are connected securely and there are no contact problems.

There are no arc marks.

A

The terminals are not connected securely and there is a contact problem.

There are arc marks.

B

The terminals are not connected securely and there is a contact problem.

There are no arc marks.

C

The terminals are connected securely and there are no contact problems.

There are arc marks.

B

(f) Reconnect the motor cable.

(g) Reinstall the inverter with converter assembly.

B

REPLACE MALFUNCTIONING PARTS
C

CONNECT SECURELY
A

4.

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

(b) Remove the inverter with converter assembly.

(c) Remove the motor cable.

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

*1

Shield Ground

-

-

*a

Motor Cable

-

-

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

p2-4 (W) or p1-3 (W) - Shield ground

Power switch off

100 MΩ or higher

p2-5 (U) or p1-2 (U) - Shield ground

Power switch off

100 MΩ or higher

p2-6 (V) or p1-1 (V) - Shield ground

Power switch off

100 MΩ or higher

NOTICE:

Wrap the terminal of the motor cable with insulating tape to prevent them from coming into contact with body ground.

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

p2-4 (W) - p1-3 (W)

Power switch off

Below 1 Ω

p2-5 (U) - p1-2 (U)

Power switch off

Below 1 Ω

p2-6 (V) - p1-1 (V)

Power switch off

Below 1 Ω

p2-4 (W) - p1-2 (U)

Power switch off

100 MΩ or higher

p2-5 (U) - p1-1 (V)

Power switch off

100 MΩ or higher

p2-6 (V) - p1-3 (W)

Power switch off

100 MΩ or higher

(f) Install the motor cable.

(g) Reinstall the inverter with converter assembly.

OK

REPLACE HYBRID VEHICLE TRANSAXLE ASSEMBLY

NG

REPLACE MOTOR CABLE