Last Modified: 11-20-2023 6.11:8.1.0 Doc ID: RM1000000012SNG
Model Year Start: 2018 Model: Camry Prod Date Range: [03/2017 - 08/2022]
Title: NETWORKING: LIN COMMUNICATION SYSTEM: B2785; Communication Malfunction between ECUs Connected by LIN; 2018 - 2022 MY Camry [03/2017 - 08/2022]

DTC

B2785

Communication Malfunction between ECUs Connected by LIN

DESCRIPTION

If the certification ECU (smart key ECU assembly) detects a communication error with an ECU connected to the certification bus lines for 7 seconds or more, DTC B2785 will be stored.

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

B2785

Communication Malfunction between ECUs Connected by LIN
  • Errors in LIN communication between ECUs or an open or short in communication lines.
  • The certification ECU (smart key ECU assembly) detects a communication error with an ECU connected to the certification bus lines for 7 seconds or more.
  • Certification ECU (Smart Key ECU assembly)
  • Steering lock ECU (Steering Lock Actuator or Upper Bracket assembly)
  • Wire harness or connector
  • STRG LOCK fuse

WIRING DIAGRAM

CAUTION / NOTICE / HINT

NOTICE:

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

    Click here 2018 - 2019 MY Camry [03/2017 - 09/2019]; THEFT DETERRENT / KEYLESS ENTRY: SMART KEY SYSTEM (for Start Function): REGISTRATION 2020 - 2022 MY Camry [09/2019 - 08/2022]; THEFT DETERRENT / KEYLESS ENTRY: SMART KEY SYSTEM (for Start Function): REGISTRATION

  • Before performing the inspection, check that DTC B2786 or B278C is not output.

    Click here 2018 - 2024 MY Camry [03/2017 -        ]; NETWORKING: LIN COMMUNICATION SYSTEM: DTC CHECK / CLEAR

  • When using the Techstream with the ignition 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 Model Code "KEY REGIST" 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.

PROCEDURE

1.

CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) - EACH ECU)

(a) Disconnect the K62 certification ECU (smart key ECU assembly) connector.

(b) Disconnect the K65 steering lock ECU (steering lock actuator or upper bracket assembly) connector.

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

NOTICE:

Make sure that each ECU is in sleep mode before performing the inspection. To enter sleep mode, turn the ignition switch from ON to off and wait for 180 seconds or more without operating any switches.

Standard Resistance:

Tester Connection

Condition

Specified Condition

K62-13 (LIN) - K65-5 (LIN)

Always

Below 1 Ω

K62-13 (LIN) or K65-5 (LIN) - Body ground

Always

10 kΩ or higher
NG

REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

2.

CHECK FOR DTC (CERTIFICATION ECU (SMART KEY ECU ASSEMBLY))

(a) Reconnect the K62 certification ECU (smart key ECU assembly) connector.

(b) Clear the DTCs.

Body Electrical > Smart Key > Clear DTCs

(c) Recheck for DTCs.

Body Electrical > Smart Key > Trouble Codes

Result

Proceed to

DTC B2785 is output

A

DTC B2785 is not output

B
A

REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) 2018 MY Camry [03/2017 - 06/2017]; THEFT DETERRENT / KEYLESS ENTRY: CERTIFICATION ECU: REMOVAL 2018 - 2020 MY Camry [06/2017 - 10/2020]; THEFT DETERRENT / KEYLESS ENTRY: CERTIFICATION ECU: REMOVAL 2021 - 2024 MY Camry [10/2020 -        ]; THEFT DETERRENT / KEYLESS ENTRY: CERTIFICATION ECU: REMOVAL

B

REPLACE STEERING LOCK ECU (STEERING LOCK ACTUATOR OR UPPER BRACKET ASSEMBLY)