Last Modified: 05-13-2024 6.11:8.1.0 Doc ID: RM1000000026PUO
Model Year Start: 2023 Model: Corolla HV Prod Date Range: [09/2022 -           ]
Title: HYBRID / BATTERY CONTROL: HYBRID CONTROL SYSTEM (for LITHIUM-ION BATTERY with PA10): Generator High-voltage Circuit; 2023 - 2025 MY Corolla HV [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:

Refer to the precautions before inspecting high voltage circuit.

Click here 2023 - 2025 MY Corolla HV [09/2022 -        ]; HYBRID / BATTERY CONTROL: HYBRID CONTROL 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 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 ignition switch to 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 ignition switch to 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

p4-4 (W) - p4-5 (U)

Ignition switch off

95.3 to 105.3 mΩ

p4-5 (U) - p4-6 (V)

Ignition switch off

95.4 to 105.4 mΩ

p4-6 (V) - p4-4 (W)

Ignition switch off

95.5 to 105.5 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

p4-4 (W) - Body ground and shield ground

Ignition switch off

100 MΩ or higher

p4-5 (U) - Body ground and shield ground

Ignition switch off

100 MΩ or higher

p4-6 (V) - Body ground and shield ground

Ignition 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 ignition switch to 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 ignition switch to 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

p4-4 (W) or p3-4 (W) - Shield ground

Ignition switch off

100 MΩ or higher

p4-5 (U) or p3-5 (U) - Shield ground

Ignition switch off

100 MΩ or higher

p4-6 (V) or p3-6 (V) - Shield ground

Ignition switch off

100 MΩ or higher

NOTICE:

Wrap the terminals 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

p4-4 (W) - p3-4 (W)

Ignition switch off

Below 1 Ω

p4-5 (U) - p3-5 (U)

Ignition switch off

Below 1 Ω

p4-6 (V) - p3-6 (V)

Ignition switch off

Below 1 Ω

p4-4 (W) - p3-5 (U)

Ignition switch off

100 MΩ or higher

p4-5 (U) - p3-6 (V)

Ignition switch off

100 MΩ or higher

p4-6 (V) - p3-4 (W)

Ignition switch off

100 MΩ or higher

(f) Reinstall the motor cable.

(g) Reinstall the inverter with converter assembly.

OK

REPLACE HYBRID VEHICLE TRANSAXLE ASSEMBLY 2023 MY Corolla Corolla Hatchback Corolla HV [09/2022 - 11/2022]; PA10 (HYBRID TRANSMISSION / TRANSAXLE): HYBRID VEHICLE TRANSAXLE: REMOVAL 2023 - 2025 MY Corolla Corolla Hatchback Corolla HV [11/2022 -        ]; PA10 (HYBRID TRANSMISSION / TRANSAXLE): HYBRID VEHICLE TRANSAXLE: REMOVAL

NG

REPLACE MOTOR CABLE 2023 MY Corolla Corolla Hatchback Corolla HV [09/2022 - 11/2022]; PA10 (HYBRID TRANSMISSION / TRANSAXLE): MOTOR CABLE: REMOVAL 2023 - 2025 MY Corolla Corolla Hatchback Corolla HV [11/2022 -        ]; PA10 (HYBRID TRANSMISSION / TRANSAXLE): MOTOR CABLE: REMOVAL