Last Modified: 07-31-2024 6.11:8.1.0 Doc ID: RM100000001CY65
Model Year Start: 2019 Model: GR Corolla Prod Date Range: [06/2018 - 09/2022]
Title: THEFT DETERRENT / KEYLESS ENTRY: SMART KEY SYSTEM (for Start Function, Gasoline Model): B2788; IG2 Signal Malfunction; 2019 - 2022 MY Corolla Corolla Hatchback GR Corolla [06/2018 - 09/2022]

DTC

B2788

IG2 Signal Malfunction

DESCRIPTION

This DTC is stored when the steering lock ECU (steering lock actuator or upper bracket assembly) detects an IG2 power supply malfunction.

HINT:

The steering lock ECU (steering lock actuator or upper bracket assembly) is not connected to the CAN communication system. However, the steering lock ECU (steering lock actuator or upper bracket assembly) is connected to the certification ECU (smart key ECU assembly) via LIN communication and communicates with other components via CAN communication through the certification ECU (smart key ECU assembly).

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

Note

B2788

IG2 Signal Malfunction

Mismatch between the steering lock ECU (steering lock actuator or upper bracket assembly) IG2 input from the LIN communication system and from the direct line. (1-trip detection logic (Only output while a malfunction is present and the engine switch is on (IG).))
  • Steering lock ECU (steering lock actuator or upper bracket assembly)
  • Wire harness or connector

DTC Output Confirmation Operation: No confirmation operation is necessary (monitoring is continuous).

Vehicle Condition and Fail-safe Function when Malfunction Detected

Vehicle Condition when Malfunction Detected

Fail-safe Function when Malfunction Detected

The steering cannot be locked or unlocked. For this reason, the engine cannot be started.

-

Related Data List and Active Test Items

DTC No.

Data List and Active Test

B2788

-

WIRING DIAGRAM

CAUTION / NOTICE / HINT

NOTICE:

  • When using the Techstream with the engine switch off, connect the Techstream to the DLC3 and turn a courtesy light switch on and off at intervals of 1.5 seconds or less until communication between the Techstream and the vehicle begins. Then select the vehicle type under manual mode and enter the following menus Body Electrical Smart Key. While using the Techstream, periodically turn a courtesy light switch on and off at intervals of 1.5 seconds or less to maintain communication between the Techstream and the vehicle.
  • The smart key system (for Start Function) uses the LIN communication system and CAN communication system. Inspect the communication function by following How to Proceed with Troubleshooting. Troubleshoot the smart key system (for Start Function) after confirming that the communication systems are functioning properly.

    Click here 2019 MY Corolla Corolla Hatchback GR Corolla [06/2018 - 01/2019]; THEFT DETERRENT / KEYLESS ENTRY: SMART KEY SYSTEM (for Start Function, Gasoline Model): HOW TO PROCEED WITH TROUBLESHOOTING 2020 - 2022 MY Corolla Corolla Hatchback GR Corolla [01/2019 - 09/2022]; THEFT DETERRENT / KEYLESS ENTRY: SMART KEY SYSTEM (for Start Function, Gasoline Model): HOW TO PROCEED WITH TROUBLESHOOTING

  • Inspect the fuses for circuits related to this system before performing the following procedure.
  • Before replacing the steering lock ECU (steering lock actuator or upper bracket assembly), refer to Registration.

    Click here 2019 MY Corolla Corolla Hatchback GR Corolla [06/2018 - 01/2019]; THEFT DETERRENT / KEYLESS ENTRY: SMART KEY SYSTEM (for Start Function, Gasoline Model): REGISTRATION 2020 MY Corolla Corolla Hatchback GR Corolla [01/2019 - 09/2019]; THEFT DETERRENT / KEYLESS ENTRY: SMART KEY SYSTEM (for Start Function, Gasoline Model): REGISTRATION 2020 MY Corolla Corolla Hatchback GR Corolla [09/2019 - 04/2020]; THEFT DETERRENT / KEYLESS ENTRY: SMART KEY SYSTEM (for Start Function, Gasoline Model): REGISTRATION 2021 - 2022 MY Corolla Corolla Hatchback GR Corolla [04/2020 - 09/2022]; THEFT DETERRENT / KEYLESS ENTRY: SMART KEY SYSTEM (for Start Function, Gasoline Model): REGISTRATION

  • After repair, confirm that no DTCs are output by performing "DTC Output Confirmation Operation".

PROCEDURE

1.

CHECK HARNESS AND CONNECTOR (POWER SOURCE)

(a) Disconnect the I59 steering lock ECU (steering lock actuator or upper bracket assembly) connector.

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

Standard Voltage:

Tester Connection

Condition

Specified Condition

I59-6 (IG2) - Body ground

Engine switch on (IG)

11 to 14 V

I59-6 (IG2) - Body ground

Engine switch off

Below 1 V

*a

Front view of wire harness connector

(to Steering Lock ECU (Steering Lock Actuator or Upper Bracket Assembly))
NG

REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

2.

CHECK HARNESS AND CONNECTOR (GROUND)

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

I59-1 (GND) - Body ground

Always

Below 1 Ω

*a

Front view of wire harness connector

(to Steering Lock ECU (Steering Lock Actuator or Upper Bracket Assembly))
OK

REPLACE STEERING LOCK ECU (STEERING LOCK ACTUATOR OR UPPER BRACKET ASSEMBLY) 2019 MY Corolla Corolla Hatchback Corolla HV GR Corolla [06/2018 - 01/2019]; STEERING COLUMN: STEERING COLUMN ASSEMBLY: DISASSEMBLY 2020 - 2022 MY Corolla Corolla Hatchback Corolla HV GR Corolla [01/2019 - 09/2022]; STEERING COLUMN: STEERING COLUMN ASSEMBLY: DISASSEMBLY

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR