Last Modified: 11-20-2023 6.11:8.1.0 Doc ID: RM1000000024JD1
Model Year Start: 2023 Model: Camry HV Prod Date Range: [08/2022 -           ]
Title: NETWORKING: LIN COMMUNICATION SYSTEM: B2785; Communication Malfunction between ECUs Connected by LIN; 2023 - 2024 MY Camry HV [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)
  • ID code box (immobiliser code ECU)
  • Wire harness or connector

WIRING DIAGRAM

CAUTION / NOTICE / HINT

NOTICE:

  • Before replacing the certification ECU (smart key ECU assembly) or ID code box (immobiliser code ECU), refer to Registration.

    Click here 2023 - 2024 MY Camry HV [08/2022 -        ]; THEFT DETERRENT / KEYLESS ENTRY: SMART KEY SYSTEM (for Start Function): REGISTRATION

  • Before performing the inspection, check that DTC B2789, B278C is not output.

    Click here 2018 - 2024 MY Camry HV [07/2017 -        ]; NETWORKING: LIN COMMUNICATION SYSTEM: DTC CHECK / CLEAR

  • When using the Techstream with the power 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) - ID CODE BOX (IMMOBILISER CODE ECU))

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

(b) Disconnect the K152 ID code box (immobiliser code ECU) 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 power switch from on (IG) to off and wait for 180 seconds or more without operating any switches.

Standard Resistance:

Tester Connection

Condition

Specified Condition

K62-13 (LIN) - K152-2 (LIN1)

Always

Below 1 Ω

K62-13 (LIN) or K152-2 (LIN1) - Body ground

Always

10 kΩ or higher
NG

REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

2.

CHECK FOR DTC

(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)

B

REPLACE ID CODE BOX (IMMOBILISER CODE ECU)