Last Modified: 01-30-2024 6.11:8.1.0 Doc ID: RM100000002EM9T
Model Year Start: 2024 Model: RAV4 Prod Date Range: [10/2023 -           ]
Title: STOP AND START: STOP AND START SYSTEM: Failure to Restart from IG-ON Engine Stall; 2024 MY RAV4 [10/2023 -        ]

Failure to Restart from IG-ON Engine Stall

DESCRIPTION

This is the troubleshooting procedure for situations where the engine does not restart when attempting to restart it after a failed engine start occurred under stop and start system control.

CAUTION / NOTICE / HINT

PRECAUTIONS WHEN THE ENGINE STOP AND START ECU AND THE STARTER ASSEMBLY ARE REPLACED

NOTICE:

  • When the engine stop and start ECU is replaced, it is necessary to read the number of starter operations before replacement and store this number in the new engine stop and start ECU after replacement, and to perform external backup boost converter (eco run vehicle converter assembly) existence learning. Moreover, initialization/learning of the air conditioning information.

    Click here 2024 MY RAV4 [10/2023 -        ]; STOP AND START: STOP AND START SYSTEM: REGISTRATION

  • When the starter assembly is replaced, the number of starter operations stored in the engine stop and start ECU must be reset.

    Click here 2024 MY RAV4 [10/2023 -        ]; STOP AND START: STOP AND START SYSTEM: REGISTRATION

  • When the starter assembly is replaced, "ST NO. 1 relay" must be also replaced.
  • Inspect the fuses for circuits related to this system before performing the following procedure.

PRECAUTIONS FOR FOUR-WHEEL TOWING

Do not tow the vehicle with all 4 wheels on the ground.

NOTICE:

  • Towing the vehicle with all 4 wheels on the ground may have a detrimental effect on the stop and start system, and could lead to damage.

HINT:

If it is absolutely necessary to tow the vehicle with all 4 wheels on the ground, before towing first turn the ignition switch off. Then, turn the ignition switch to ON without starting the engine, and tow the vehicle.

PRECAUTIONS WHEN REPLACING ECM

NOTICE:

When the ECM is replaced on a vehicle with a non-specified battery, it is necessary to perform battery type switching.

Click here 2024 MY RAV4 [10/2023 -        ]; STOP AND START: STOP AND START SYSTEM: REGISTRATION

PROCEDURE

1.

CHECK VEHICLE CONTROL HISTORY (FAILURE TO RESTART FROM IG-ON ENGINE STALL)

(a) Enter the following menus: Powertrain / Stop and Start / Utility / Vehicle Control History (RoB).

Powertrain > Stop and Start > Utility

Tester Display

Vehicle Control History (RoB)

(b) Check vehicle control history.

HINT:

  • Checking the Freeze Frame Data allows the vehicle conditions at the time of detection to be confirmed.
  • As Vehicle Control History may be overwritten whenever the trigger conditions are met, make sure to save the Vehicle Control History data before performing any inspections.

Result

Proceed to

Vehicle control history [X0874: Stop & Start Restart Failure (Engine Restart after Engine Stall)] is output

A

Vehicle control history [X0874: Stop & Start Restart Failure (Engine Restart after Engine Stall)] is not output

B
B

GO TO SFI SYSTEM (ROB CHART)

Diagnostic trouble code chart :

Click here 2024 MY RAV4 RAV4 HV [10/2023 -        ]; A25A-FKS (ENGINE CONTROL): SFI SYSTEM: DIAGNOSTIC TROUBLE CODE CHART

Vehicle control history (RoB):

Click here 2022 - 2024 MY RAV4 RAV4 HV [12/2021 -        ]; A25A-FKS (ENGINE CONTROL): SFI SYSTEM: VEHICLE CONTROL HISTORY (RoB)

A

2.

CUSTOMER PROBLEM ANALYSIS AND SYMPTOM CONFIRMATION

(a) Consult with the customer to determine if they performed operations that could result in an AT engine stall.

HINT:

(ex.) Heavy load, frequent shifts, etc.

Result

Proceed to

Driver operations that could cause engine stall were performed

A

None of the above conditions are met

B
A

ENGINE STALL DUE TO DRIVER OPERATION
B

3.

CHECK VEHICLE CONTROL HISTORY AND PROBLEM SYMPTOMS

(a) Enter the following menus: Powertrain / Stop and Start / Utility / Vehicle Control History (RoB).

Powertrain > Stop and Start > Utility

Tester Display

Vehicle Control History (RoB)

(b) Select a vehicle control history item to display the data from the time of control.

(c) Check the output data.

HINT:

  • Checking the Freeze Frame Data allows the vehicle conditions at the time of detection to be confirmed.
  • As Vehicle Control History may be overwritten whenever the trigger conditions are met, make sure to save the Vehicle Control History data before performing any inspections.

Result

Proceed to

All recorded sections Starter Motor = OFF, and all recorded sections Engine Speed = 0 rpm

HINT:

It is possible that the starter drive command is not being sent from the engine stop and start ECU.

A

Starter Motor = ON for any sections, and all recorded sections Engine Speed = 0 rpm

HINT:

It is possible that the drive command is being sent from the engine stop and start ECU but the starter itself is not moving.

B

Engine Speed > 0 rpm for any sections

HINT:

It is possible that cranking was achieved but the engine stopped.

C
A

REPLACE ENGINE STOP AND START ECU

HINT:

It is possible that there is a malfunction of the starter drive circuit inside the stop and start ECU.
C

GO TO STEP 8

B

4.

CHECK VEHICLE CONTROL HISTORY AND PROBLEM SYMPTOMS

(a) Enter the following menus: Powertrain / Stop and Start / Utility / Vehicle Control History (RoB).

Powertrain > Stop and Start > Utility

Tester Display

Vehicle Control History (RoB)

(b) Select a vehicle control history item to display the data from the time of control.

(c) Check the output data.

HINT:

  • Checking the Freeze Frame Data allows the vehicle conditions at the time of detection to be confirmed.
  • As Vehicle Control History may be overwritten whenever the trigger conditions are met, make sure to save the Vehicle Control History data before performing any inspections.

Result

Proceed to

Cranking Time is 1.5 seconds or more

HINT:

It is possible that there is an external malfunction outside of the stop and start ECU (drive circuit).

A

Cranking Time is less than 1.5 seconds

HINT:

It is possible that there is a malfunction in the stop and start ECU (drive circuit).

B
B

REPLACE ENGINE STOP AND START ECU

A

5.

CHECK ENGINE STOP AND START ECU (+B VOLTAGE)

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

(b) Turn the ignition switch to ON.

(c) Turn off any electrical loads.

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

Standard Voltage:

Tester Connection

Switch Condition

Specified Condition

A25-1 (+B) - Body ground

Ignition switch ON

11 V or higher
NG

GO TO STEP 7

OK

6.

CHECK VEHICLE CONTROL HISTORY (BATTERY VOLTAGE)

(a) Enter the following menus: Powertrain / Stop and Start / Utility / Vehicle Control History (RoB).

Powertrain > Stop and Start > Utility

Tester Display

Vehicle Control History (RoB)

(b) Select a vehicle control history item to display the data from the time of control.

(c) Check the output data.

HINT:

  • Checking the Freeze Frame Data allows the vehicle conditions at the time of detection to be confirmed.
  • As Vehicle Control History may be overwritten whenever the trigger conditions are met, make sure to save the Vehicle Control History data before performing any inspections.
  • Depending on RoB detection timing, the minimum voltage from the previous startup will be stored for the Minimum Voltage (Cranking) and the Minimum Voltage (Starter Solenoid Engagement). For the battery condition at the start of the current driving cycle, see Battery Voltage.
  • When the value is 20 V, the value is being calculated.

Result

Proceed to

Battery voltage is 8.92 V or more

A

Battery voltage is less than 8.92 V

B
A

INSPECT STARTER SYSTEM

B

GO TO STEP 7

7.

INSPECT BATTERY

(a) Measure the voltage of the battery.

Standard voltage:

11 to 14 V

OK

INSPECT STARTER SYSTEM

NG

REPLACE BATTERY

8.

CHECK VEHICLE CONTROL HISTORY (CRANKING TIME AND STARTER OFF PERMISSION HISTORY (ECM))

(a) Enter the following menus: Powertrain / Stop and Start / Utility / Vehicle Control History (RoB).

Powertrain > Stop and Start > Utility

Tester Display

Vehicle Control History (RoB)

(b) Select a vehicle control history to display the "Cranking Time" and "Starter OFF Permission History (ECM)" data from the time of control.

(c) Check the output data.

HINT:

  • Checking the Freeze Frame Data allows the vehicle conditions at the time of detection to be confirmed.
  • As Vehicle Control History may be overwritten whenever the trigger conditions are met, make sure to save the Vehicle Control History data before performing any inspections.

Result

Proceed to

"Cranking Time" is less than 1.5 seconds

"Starter OFF Permission History (ECM)" is ON

HINT:

It is possible that the ECM made a judgment of complete combustion and the ECM then stopped the starter.

A

"Starter OFF Permission History (ECM)" is OFF

HINT:

It is possible that the engine stop and start ECU made a judgment of complete combustion and the engine stop and start ECU then stopped the starter.

B

"Cranking Time" is 1.5 seconds or more

HINT:

It is possible that the stop and start ECU did not stop the starter.

-

C
A

SFI SYSTEM (POOR STARTABILITY)

HINT:

Check whether the speed value of the EFI ECU is not a higher value than the original NE.
C

GO TO STEP 12

B

9.

READ VALUE USING GTS (ENGINE SPEED AND ENGINE SPEED (ECM))

(a) Enter the following menus: Powertrain / Stop and Start / Data List / Engine Speed and Engine Speed (ECM).

Powertrain > Stop and Start > Data List

Tester Display

Engine Speed

Engine Speed (ECM)

(b) Compare the Data List items displayed on the GTS.

Result

Proceed to

Engine Speed > Engine Speed (ECM) + 100 rpm

A

None of the above conditions are met

B
B

GO TO STEP 11

A

10.

CHECK DATA POINTS (ENGINE SPEED AND ENGINE SPEED (ECM))

(a) Enter the following menus: Powertrain / Stop and Start / Utility / Vehicle Control History (RoB).

Powertrain > Stop and Start > Utility

Tester Display

Vehicle Control History (RoB)

(b) Select a vehicle control history item to display the data from the time of control.

(c) Check the data points in the data that was output.

HINT:

  • Checking the Freeze Frame Data allows the vehicle conditions at the time of detection to be confirmed.
  • As Vehicle Control History may be overwritten whenever the trigger conditions are met, make sure to save the Vehicle Control History data before performing any inspections.

Result

Proceed to

For each and all of the data points, "Engine Speed" > "Engine Speed (ECM)" + 100 rpm

A

None of the above conditions are met

B
A

READ VALUE USING GTS (ENGINE SPEED)

B

GO TO STEP 11

11.

CHECK ENGINE STOP AND START ECU (STA SIGNAL)

*a

Component with harness connected

(Engine Stop and Start ECU)

-

-

(a) Enter the following menus: Powertrain / Stop and Start / Active Test / Starter (Hood Close)

Powertrain > Stop and Start > Active Test

Tester Display

Starter(Hood Close)

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

Click here 2024 MY RAV4 [10/2023 -        ]; STOP AND START: STOP AND START SYSTEM: TERMINALS OF ECU

Standard Voltage:

Tester Connection

Condition

Specified Condition

A25-21 (STA) - A25-6 (DGND)

Performing Active Test, while cranking.

6 to 14 V

(c) Using an oscilloscope, measure the waveform immediately after starting.

Item

Content

Tester Connection

A25-21 (STA) ←→ A25-6 (DGND)

Tool Setting

10 V/DIV, 200 ms./DIV

Condition

During cranking

OK:

Voltage and waveform both normal
OK

INSPECT ENGINE (SFI SYSTEM, POOR STARTABILITY)

NG

REPLACE ENGINE STOP AND START ECU

12.

CHECK DATA POINTS (ENGINE SPEED)

(a) Enter the following menus: Powertrain / Stop and Start / Utility / Vehicle Control History (RoB).

(b) Select a vehicle control history item to display the data from the time of control.

(c) Check the output data.

HINT:

  • Checking the Freeze Frame Data allows the vehicle conditions at the time of detection to be confirmed.
  • As Vehicle Control History may be overwritten whenever the trigger conditions are met, make sure to save the Vehicle Control History data before performing any inspections.

Result

Proceed to

When Starter Motor is ON, there is even 1 point at which Engine Speed < 300 rpm

A

None of the above conditions are met

B
A

INSPECT STARTER SYSTEM

B

13.

CHECK OPERATION

(a) Check how long it took the engine to stall after turning the starter off.

Result

Proceed to

After starter turned off, engine immediately stalls.

HINT:

Engine stalls within 2 seconds.

A

After starter turned off, engine stalls after a time.

B
A

SFI SYSTEM (ENGINE DIFFICULT TO START)

B

SFI SYSTEM (ENGINE STALLS)