HYBRID / BATTERY CONTROL: MOTOR GENERATOR CONTROL SYSTEM (for LITHIUM-ION BATTERY with P610): P0CA300; DC/DC Converter Step Up Voltage Performance; 2021 - 2022 MY Corolla Corolla HV [04/2020

This DTC indicates that it has been detected that the VH voltage cannot be boosted as commanded due to malfunction of the boost converter system. The cause of this malfunction may be one of the following:

DESCRIPTION

The boost converter boosts the 207.2 V DC from the HV battery to a maximum of approximately 600 V DC. The inverter converts the voltage that has been boosted by the boost converter into alternating current, which is used for driving generator (MG1) and motor (MG2). When a motor or generator operates as a generator, the alternating current that it creates is converted into direct current by the inverter. Then the boost converter drops this voltage to direct current of approximately 207.2 V in order to charge the HV battery.

The motor generator control ECU (MG ECU) uses a voltage sensor (VL) that is built into the boost converter to detect the high voltage before it is boosted. It also uses a voltage sensor (VH) that is built into the inverter to detect the high voltage after it is boosted. Based on the voltage before and after it is boosted, the motor generator control ECU (MG ECU) controls the operation of the boost converter to boost the voltage to the target voltage.

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

With the shift lever in P, depress the brake pedal firmly, and quickly and fully depress the accelerator pedal.

Immediately after the accelerator pedal is fully depressed, "VH-Voltage after boosting" will be between 400 and 600 V.

Related Data List

MONITOR DESCRIPTION

If the difference between the requested boost converter voltage and the actual boost converter voltage exceeds a predetermined value, the motor generator control ECU determines that there is a malfunction of the execution or monitoring of the boost converter voltage. The motor generator control ECU will illuminate the MIL and store a DTC.

MONITOR STRATEGY

TYPICAL ENABLING CONDITIONS

TYPICAL MALFUNCTION THRESHOLDS

COMPONENT OPERATING RANGE

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.
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When clearing the permanent DTCs, refer to the "CLEAR PERMANENT DTC" procedure.
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Connect the Techstream to the DLC3.
Turn the power switch on (IG) and turn the Techstream on.
Clear the DTCs (even if no DTCs are stored, perform the clear DTC procedure).
Turn the power switch off and wait for 2 minutes or more.
Turn the power switch on (IG) and turn the Techstream on.
With the power switch on (IG) and wait for 5 seconds or more. [*1]
Turn the power switch on (READY) and wait for 5 seconds or more. [*2]
Depress the accelerator pedal of the vehicle with the engine stopped and the shift lever in P to start the engine. [*3]
NOTICE:

As the state of charge of the HV battery may be low after driving in fail-safe mode, it will automatically be charged for 5 to 10 minutes with power switch on (READY) after repairs have been performed.

HINT:

[*1] to [*3]: Normal judgment procedure.

The normal judgment procedure is used to complete DTC judgment and also used when clearing permanent DTCs.
Enter the following menus: Powertrain / Motor Generator / Utility / All Readiness.
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.

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.

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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

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.

PROCEDURE

Powertrain > Hybrid Control > Trouble Codes

Powertrain > Motor Generator > Trouble Codes

Table 1

Table 2

HINT:

P0CA300 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.)

DTC SUMMARY

Internal inverter malfunction

Inverter low-voltage circuit malfunction

DESCRIPTION

Related Data List

MONITOR DESCRIPTION

MONITOR STRATEGY

TYPICAL ENABLING CONDITIONS

TYPICAL MALFUNCTION THRESHOLDS

COMPONENT OPERATING RANGE

CONFIRMATION DRIVING PATTERN

CAUTION / NOTICE / HINT

PROCEDURE

Powertrain > Hybrid Control > Trouble Codes

Powertrain > Motor Generator > Trouble Codes

Table 1

Table 2