Last Modified: 05-13-2024 6.11:8.1.0 Doc ID: RM100000001GCL0
Model Year Start: 2020 Model: Corolla Prod Date Range: [01/2019 - 09/2022]
Title: HYBRID / BATTERY CONTROL: HYBRID CONTROL SYSTEM (for NICKEL METAL HYDRIDE BATTERY): P1CFA12; IGB Signal Circuit Short to Auxiliary Battery; 2020 - 2022 MY Corolla Corolla HV [01/2019 - 09/2022]

DTC

P1CFA12

IGB Signal Circuit Short to Auxiliary Battery

DESCRIPTION

The hybrid vehicle control ECU monitors the IGB signal received from the certification ECU (smart key ECU assembly). When an error is detected in the IGB signal, this DTC is stored.

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

MIL

Warning Indicate

P1CFA12

IGB Signal Circuit Short to Auxiliary Battery

An IGB signal from the hybrid vehicle control ECU is on when the power switch is off.

(1 trip detection logic)

  • Wire harness or connector
  • Hybrid vehicle control ECU
  • Certification ECU (smart key ECU assembly)

Does not come on

Master Warning: Comes on

CONFIRMATION DRIVING PATTERN

HINT:

After repair has been completed, clear the DTCs and then check that the vehicle has returned to normal by performing the following All Readiness check procedure.

Click here 2020 - 2022 MY Corolla Corolla HV [01/2019 - 09/2022]; HYBRID / BATTERY CONTROL: HYBRID CONTROL SYSTEM (for NICKEL METAL HYDRIDE BATTERY): UTILITY

  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 2 minutes or more.
  5. Turn the power switch on (IG) and turn the Techstream on.
  6. Enter the following menus: Powertrain / Hybrid Control / Utility / All Readiness.
  7. 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 driving pattern again.

WIRING DIAGRAM

CAUTION / NOTICE / HINT

NOTICE:

Before replacing the certification ECU (smart key ECU assembly), refer to Registration.

Click here 2020 MY Corolla Corolla HV [01/2019 - 04/2020]; THEFT DETERRENT / KEYLESS ENTRY: SMART KEY SYSTEM (for Start Function, HV Model): REGISTRATION 2021 - 2022 MY Corolla Corolla HV [04/2020 - 09/2022]; THEFT DETERRENT / KEYLESS ENTRY: SMART KEY SYSTEM (for Start Function, HV Model): REGISTRATION

PROCEDURE

1.

CHECK CONNECTOR CONNECTION CONDITION (HYBRID VEHICLE CONTROL ECU CONNECTOR)

Click here 2020 - 2022 MY Corolla Corolla HV [01/2019 - 09/2022]; HYBRID / BATTERY CONTROL: HYBRID CONTROL SYSTEM (for NICKEL METAL HYDRIDE BATTERY): P056014; System Voltage (BATT) Circuit Short to Ground or Open+

NG

CONNECT SECURELY

OK

2.

CHECK CONNECTOR CONNECTION CONDITION (CERTIFICATION ECU (SMART KEY ECU ASSEMBLY))

(a) Check the connector connection condition of the certification ECU (smart key 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.

NG

CONNECT SECURELY

OK

3.

CHECK HARNESS AND CONNECTOR (IGB TERMINAL VOLTAGE)

(a) Turn the power switch off.

(b) Measure the voltage according to the value(s) in the table below.

*a

Component with harness connected

(Hybrid Vehicle Control ECU)

-

-

Standard Voltage:

Tester Connection

Condition

Specified Condition

I3-44 (IGB) - Body ground

Power switch off

Below 1 V

OK

REPLACE HYBRID VEHICLE CONTROL ECU 2020 MY Corolla Corolla HV [01/2019 - 04/2020]; HYBRID / BATTERY CONTROL: HYBRID VEHICLE CONTROL ECU: REMOVAL 2021 - 2022 MY Corolla Corolla HV [04/2020 - 09/2022]; HYBRID / BATTERY CONTROL: HYBRID VEHICLE CONTROL ECU: REMOVAL

NG

4.

CHECK HARNESS AND CONNECTOR (HYBRID VEHICLE CONTROL ECU - CERTIFICATION ECU (SMART KEY ECU ASSEMBLY))

(a) Disconnect the I1 certification ECU (smart key ECU assembly) connector.

(b) Measure the voltage according to the value(s) in the table below.

*a

Component with harness connected

(Hybrid Vehicle Control ECU)

-

-

Standard Voltage:

Tester Connection

Condition

Specified Condition

I3-44 (IGB) - Body ground

Power switch off

Below 1 V

(c) Reconnect the I1 certification ECU (smart key ECU assembly) connector.

OK

REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) 2020 MY Corolla Corolla Hatchback Corolla HV GR Corolla [01/2019 - 03/2019]; THEFT DETERRENT / KEYLESS ENTRY: CERTIFICATION ECU: REMOVAL 2020 - 2022 MY Corolla Corolla Hatchback Corolla HV GR Corolla [03/2019 - 09/2022]; THEFT DETERRENT / KEYLESS ENTRY: CERTIFICATION ECU: REMOVAL

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR