STOP AND START: STOP AND START SYSTEM: P094296; Hydraulic Pressure Unit Component Internal Failure; 2020 - 2023 MY RAV4 [10/2019

Last Modified: 01-30-2024	6.11:8.1.0	Doc ID: RM100000001KNE7
Model Year Start: 2020	Model: RAV4	Prod Date Range: [10/2019 - 10/2023]
Title: STOP AND START: STOP AND START SYSTEM: P094296; Hydraulic Pressure Unit Component Internal Failure; 2020 - 2023 MY RAV4 [10/2019 - 10/2023]

DTC

P094296

Hydraulic Pressure Unit Component Internal Failure

DESCRIPTION

Refer to DTC P279612.

Click here

DTC No.	Detection Item	DTC Detection Condition	Trouble Area	Warning Indicate	Memory	Note
P094296	Hydraulic Pressure Unit Component Internal Failure	The following condition continues for 0.032 seconds or more (2 trip detection logic): Difference between turbine speed and output shaft speed is 330 rpm or more within 0.2 seconds after engine restarted during idling stop when shift lever is in D.	Oil pump with solenoid assembly Engine stop and start ECU	Blinks	DTC stored	SAE Code: P0942

CONFIRMATION DRIVING PATTERN

CONFIRMATION AFTER TROUBLESHOOTING

HINT:

If the cable is disconnected from the battery terminal, stop and start control is prohibited until refresh charge is completed.
In this case, let the vehicle idle to complete the refresh charge. The refresh charge is complete when the Data List item "Status of Battery Charge Control" changes from "Refresh Charge Mode". (Usually, idling the engine for 5 to 60 minutes with the battery fluid temperature at 11°C (51°F) or higher, the refresh charge will be completed.)
If the Techstream is not available and the Data List item "Status of Battery Charge Control" cannot be checked, charge the battery by idling the engine for approximately 5 to 60 minutes or driving the vehicle, and then drive the vehicle and check that stop and start control operates.
If the engine is started with the hood open, the system determines that a jump start has occurred. Therefore, make sure that the hood is closed before starting the engine and driving the vehicle.
After the refresh charge completes, turn the ignition switch off, wait for at least 30 seconds, and then start the engine again. If the vehicle enters refresh charge mode again while the engine is idling, the initial refresh charge did not properly complete, so wait for the refresh charge to complete.
Allow the engine to idle for 3 minutes after it is warmed up and check that the engine idle speed is within 50 rpm of the target idle speed.

(a) Connect the Techstream to the DLC3.

(b) Turn the ignition switch to ON.

(d) Clear the DTCs.

Powertrain > Stop and Start > Clear DTCs

(e) Start the engine and warm it up.

(f) Drive the vehicle at 7 km/h (4 mph) or more.

CAUTION:

When performing Confirmation Driving Pattern, obey all speed limits and traffic laws.

(g) Depress the brake pedal and stop the vehicle.

(h) Keep the engine stopped by stop and start control. (Keep the shift lever in D.)

(i) Release the brake pedal with the shift lever in D to start the engine.

(j) Check that no DTCs are output.

Powertrain > Stop and Start > Trouble Codes

STOP AND START SYSTEM OPERATION CHECK

HINT:

If the cable is disconnected from the battery terminal, stop and start control is prohibited until refresh charge is completed.
In this case, let the vehicle idle to complete the refresh charge. The refresh charge is complete when the Data List item "Status of Battery Charge Control" changes from "Refresh Charge Mode". (Usually, idling the engine for 5 to 60 minutes with the battery fluid temperature at 11°C (51°F) or higher, the refresh charge will be completed.)
If the Techstream is not available and the Data List item "Status of Battery Charge Control" cannot be checked, charge the battery by idling the engine for approximately 5 to 60 minutes or driving the vehicle, and then drive the vehicle and check that stop and start control operates.
If the engine is started with the hood open, the system determines that a jump start has occurred. Therefore, make sure that the hood is closed before starting the engine and driving the vehicle.
After the refresh charge completes, turn the ignition switch off, wait for at least 30 seconds, and then start the engine again. If the vehicle enters refresh charge mode again while the engine is idling, the initial refresh charge did not properly complete, so wait for the refresh charge to complete.

(a) Start the engine and warm it up.

(b) Turn the air conditioning system off.

CAUTION:

When performing Confirmation Driving Pattern, obey all speed limits and traffic laws.

(d) Depress the brake pedal and stop the vehicle.

(e) Allow the engine to stop by stop and start control. (Keep the shift lever in D.)

(f) Release the brake pedal with the shift lever in D to start the engine.

WIRING DIAGRAM

Refer to DTC P279612.

Click here

CAUTION / NOTICE / HINT

NOTICE:

Before replacing the engine stop and start ECU, read the number of starter operations and write it into a new engine stop and start ECU.
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After replacing the engine stop and start ECU or air conditioning amplifier assembly, reset and perform learning of the air conditioning information in the engine stop and start ECU.
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After replacing the engine stop and start ECU or airbag ECU assembly, clear and calibrate the deceleration sensor zero point in the engine stop and start ECU.
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When the engine stop and start ECU or oil pump with solenoid assembly is replaced, check the oil pump with solenoid assembly.
Click here

HINT:

Using the Techstream, read the freeze frame data before troubleshooting. System condition information is recorded as freeze frame data the moment a DTC is stored. This information can be useful when troubleshooting.
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DTCs for the stop and start system are not cleared even if the malfunction has been repaired. After repairing the malfunction, be sure to clear the DTCs.
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PROCEDURE

1.	CHECK ENGINE STOP AND START ECU (EMOP AND EGND TERMINAL WAVEFORM)

(a) Drive the vehicle to warm up the engine and automatic transaxle fluid.

HINT:

The oil pump with solenoid assembly may not operate properly if the automatic transaxle fluid temperature is low. Make sure to warm up the automatic transaxle fluid before performing the Active Test. (Automatic transaxle fluid temperature: 25°C (77°F) or higher)

(b) Connect the Techstream to the DLC3.

HINT:

Do not start the engine.

(d) Turn the Techstream on.

(e) Connect an oscilloscope to the EGND and GND1 terminals of the engine stop and start ECU connector.

Component with harness connected

(Engine Stop and Start ECU)

(f) Enter the following menus: Powertrain / Stop and Start / Active Test / Electromagnetic Oil Pump.

Powertrain > Stop and Start > Active Test

Tester Display
Electromagnetic Oil Pump

(g) Check the waveform while performing the Active Test.

Item	Condition
Tester Connection	A32-8 (EGND) - A33-8 (GND1)
Tool Setting	10 V/DIV., 20 ms./DIV.
Condition	Ignition switch ON (engine is stopped) Active Test "Electromagnetic Oil Pump" being performed

Standard:

The waveform is similar to that shown in the illustration.

Result:

Proceed to
OK
NG

REPLACE OIL PUMP WITH SOLENOID ASSEMBLY

for 2WD:
Click here
for AWD:
Click here

CLEAR DTC

(a) Connect the Techstream to the DLC3.

(b) Turn the ignition switch to ON.

(d) Enter the following menus: Powertrain / Stop and Start / Trouble Codes.

(e) Clear the DTCs.

Powertrain > Stop and Start > Clear DTCs

3.	CHECK DTC OUTPUT

(a) Start the engine.

(b) Perform a road test.

(d) Read the DTCs.

Powertrain > Stop and Start > Trouble Codes

Result	Proceed to
DTC P094296 is output	A
DTC P094296 is not output	B

REPLACE ENGINE STOP AND START ECU

USE SIMULATION METHOD TO CHECK