Last Modified: 01-30-2024 6.11:8.1.0 Doc ID: RM100000002FQY9
Model Year Start: 2024 Model: RAV4 Prod Date Range: [10/2023 -           ]
Title: NETWORKING: CAN COMMUNICATION SYSTEM (for Gasoline Model): Engine Stop and Start ECU Communication Stop Mode; 2024 MY RAV4 [10/2023 -        ]

Engine Stop and Start ECU Communication Stop Mode

DESCRIPTION

Detection Item

Symptom

Trouble Area

Engine Stop and Start ECU Communication Stop Mode

Any of the following conditions are met:

  • Communication stop for "Stop and Go/Start" is indicated on the "Communication Bus Check" screen of the Techstream.

    Click here 2022 - 2024 MY RAV4 [12/2021 -        ]; NETWORKING: CAN COMMUNICATION SYSTEM (for Gasoline Model): PROBLEM SYMPTOMS TABLE

  • Communication stop history for "Stop and Go/Start" is indicated on the "Communication Bus Check (Detail)" screen of the Techstream. (The Lost Communication Time value for "Stop and Go/Start" is 6 or more.)

    Click here 2022 - 2024 MY RAV4 [12/2021 -        ]; NETWORKING: CAN COMMUNICATION SYSTEM (for Gasoline Model): PROBLEM SYMPTOMS TABLE

  • Communication system DTCs (DTCs that start with U) that correspond to "Engine Stop and Start ECU Communication Stop Mode" in "DTC Combination Table" are output.

    Click here 2024 MY RAV4 [10/2023 -        ]; NETWORKING: CAN COMMUNICATION SYSTEM (for Gasoline Model): DTC COMBINATION TABLE

  • Engine stop and start ECU branch wire or connector
  • Power source circuit of engine stop and start ECU
  • Engine stop and start ECU ground circuit
  • Engine stop and start ECU

WIRING DIAGRAM

CAUTION / NOTICE / HINT

CAUTION:

When performing the confirmation driving pattern, obey all speed limits and traffic laws.

NOTICE:

  • Because the order of diagnosis is important to allow correct diagnosis, make sure to begin troubleshooting using How to Proceed with Troubleshooting when CAN communication system related DTCs are output.

    Click here 2019 - 2024 MY RAV4 [11/2018 -        ]; NETWORKING: CAN COMMUNICATION SYSTEM (for Gasoline Model): HOW TO PROCEED WITH TROUBLESHOOTING

  • Inspect the fuses for circuits related to this system before performing the following procedure.
  • Before measuring the resistance of the CAN bus, turn the ignition switch off and leave the vehicle for 1 minute or more without operating the key or any switches, or opening or closing the doors. After that, disconnect the cable from the negative (-) battery terminal and leave the vehicle for 1 minute or more before measuring the resistance.
  • After turning the ignition switch off, waiting time may be required before disconnecting the cable from the negative (-) battery terminal. Therefore, make sure to read the disconnecting the cable from the negative (-) battery terminal notices before proceeding with work.

    Click here 2019 - 2024 MY RAV4 RAV4 HV [11/2018 -        ]; INTRODUCTION: REPAIR INSTRUCTION: PRECAUTION

  • Some parts must be initialized and set when replacing or removing and installing parts.

    Click here 2024 MY RAV4 RAV4 HV [10/2023 -        ]; INTRODUCTION: REPAIR INSTRUCTION: INITIALIZATION

  • After performing repairs, perform the DTC check procedure and confirm that the DTCs are not output again.

    DTC check procedure: Turn the ignition switch to ON and wait for 1 minute or more. Then operate the suspected malfunctioning system and drive the vehicle at 60 km/h (37 mph) or more for 5 minutes or more.

  • After the repair, perform the CAN bus check and check that all the ECUs and sensors connected to the CAN communication system are displayed as normal.

    Click here 2024 MY RAV4 [10/2023 -        ]; NETWORKING: CAN COMMUNICATION SYSTEM (for Gasoline Model): DIAGNOSIS SYSTEM

HINT:

  • Before disconnecting related connectors for inspection, push in on each connector body to check that the connector is not loose or disconnected.
  • When a connector is disconnected, check that the terminals and connector body are not cracked, deformed or corroded.

PROCEDURE

1.

CHECK FOR OPEN IN CAN BUS WIRE (ENGINE STOP AND START ECU BRANCH WIRE)

(a) Disconnect the cable from the negative (-) battery terminal.

(b) Disconnect the engine stop and start ECU connector.

*a

Front view of wire harness connector

(to Engine Stop and Start ECU)

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

A32-13 (CANH) - A32-14 (CANL)

Cable disconnected from negative (-) battery terminal

54 to 69 Ω
NG

REPAIR OR REPLACE CAN BRANCH WIRE OR CONNECTOR
OK

2.

CHECK HARNESS AND CONNECTOR (POWER SOURCE CIRCUIT)

(a) Disconnect the engine stop and start ECU connectors.

*a

Front view of wire harness connector

(to Engine Stop and Start ECU)

-

-

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

A33-2 (GND2) - Body ground

Cable disconnected from negative (-) battery terminal

Below 1 Ω

A33-8 (GND1) - Body ground

Cable disconnected from negative (-) battery terminal

Below 1 Ω

A34-6 (DGND) - Body ground

Cable disconnected from negative (-) battery terminal

Below 1 Ω

(c) Reconnect the cable to the negative (-) battery terminal.

NOTICE:

When disconnecting the cable, some systems need to be initialized after the cable is reconnected.

Click here 2024 MY RAV4 RAV4 HV [10/2023 -        ]; INTRODUCTION: REPAIR INSTRUCTION: INITIALIZATION

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

Standard Voltage:

Tester Connection

Condition

Specified Condition

A34-1 (+B) - Body ground

Always

9.5 to 14 V

A33-1 (BIN2) - Body ground

Always

9.5 to 14 V

A33-3 (BIN1) - Body ground

Always

9.5 to 14 V

A32-21 (IGR) - Body ground

Ignition switch ON

9.5 to 14 V

Ignition switch off

Below 1 V

A32-18 (IGP) - Body ground

Ignition switch ON

9.5 to 14 V

Ignition switch off

Below 1 V

A32-19 (ACC) - Body ground

Ignition switch ACC

9.5 to 14 V

Ignition switch off

Below 1 V
OK

REPLACE ENGINE STOP AND START ECU

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR (POWER SOURCE CIRCUIT)