ENTRY AND START SYSTEM (for Start Function) Power Source Mode does not Change to ON (IG and ACC)

DESCRIPTION

If any of the following operations are performed, the certification ECU (smart key ECU assembly) receives a signal, and changes the power source mode.

With the electrical key transmitter sub-assembly in the cabin, the engine switch is pressed.
When the battery of the electrical key transmitter sub-assembly is depleted, the brake pedal is depressed and the electrical key transmitter sub-assembly is held near the engine switch.
When the entry cancel function has been canceled through the customized parameters, the brake pedal is depressed and the electrical key transmitter sub-assembly is held near the engine switch.

Tech Tips

When the cable is disconnected and reconnected to the negative (-) battery terminal, the power source mode returns to the state it was in before the cable was disconnected.
If the room oscillator does not recognize the key, the cause of the malfunction may be stored in the certification ECU (smart key ECU assembly).
If the cause of the malfunction is stored in the certification ECU (smart key ECU assembly), the following table is helpful in checking whether or not the malfunction was caused by wave interference.

Radio Wave Interference:
Problem Symptom	Data List Item
Operating Engine Switch / Key RF Signal Interference	When the engine switch was operated, the electrical key transmitter sub-assembly could not be confirmed due to wave interference. Therefore, the output frequency was switched to the other channel (changed from channel 1 to channel 2 or from channel 2 to channel 1). If the cause of the malfunction has not been stored but any devices that can cause wave interference in the cabin have been removed and the room oscillator successfully recognizes the key, the possibility of wave interference is high.

Related Data List and Active Test Items
Problem Symptom	Data List Item	Active Test Item
Power source mode does not change to on (IG) or on (ACC)	Power Source Control Start Switch1 Start Switch2 Power Supply Condition IG1 Relay Monitor(Inside) IG2 Relay Monitor(Inside) IG1 Relay Monitor(Outside) IG2 Relay Monitor(Outside) Latch Circuit ACC Relay Monitor	-

WIRING DIAGRAM

INSPECTION PROCEDURE

Note

When using the GTS with the engine switch off to troubleshoot:

Connect the GTS to the DLC3 and turn a courtesy light switch on and off at 1.5 second intervals until communication between the GTS and vehicle begins.
The entry and start system (for Start Function) uses a multiplex communication system (LIN communication system) and the CAN communication system. Inspect the communication function by following How to Proceed with Troubleshooting Click here. Troubleshoot the entry and start system (for Start Function) after confirming that the communication systems are functioning properly.
Make sure that no DTCs are output. If any DTCs are output, proceed to the Diagnostic Trouble Code Chart Click here.
If the entry and start system is disabled through the customize function, enable the system before performing troubleshooting Click here.
Before replacing the certification ECU (smart key ECU assembly), electrical key transmitter sub-assembly or ID code box (immobiliser code ECU), refer to the entry and start system (for Start Function) precaution Click here.
Inspect the fuses of circuits related to this system before performing the following inspection procedure.
After completing repairs, confirm that the problem does not occur.

PROCEDURE

CHECK WIRELESS DOOR LOCK CONTROL SYSTEM
1. Check the wireless door lock function by operating the electrical key transmitter sub-assembly.
  
  OK
  
  Wireless door lock function operates.
NG
GO TO OTHER FLOWCHART (All Door Entry Lock/Unlock Functions and Wireless Functions do not Operate) Click here

OK

OK
Wireless door lock function operates.

CHECK HARNESS AND CONNECTOR (POWER SOURCE)

Text in Illustration
*a	Rear view of wire harness connector (to Certification ECU (smart key ECU assembly))

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

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

Standard Voltage

Tester Connection	Condition	Specified Condition
A34-2 (+B) - Body ground	Always	11 to 14 V

REPAIR OR REPLACE HARNESS OR CONNECTOR IN CIRCUIT CONNECTED TO POWER SOURCE

CHECK HARNESS AND CONNECTOR (GROUND)

Text in Illustration
*a	Rear view of wire harness connector (to Certification ECU (smart key ECU assembly))

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

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

Standard Resistance

Tester Connection	Condition	Specified Condition
A34-11 (E) - Body ground	Always	Below 1 Ω

REPAIR OR REPLACE HARNESS OR CONNECTOR

CHECK PUSH-BUTTON START FUNCTION

Remove the battery from the electrical key transmitter sub-assembly Click here.

Text in Illustration
*1	Engine Switch
*2	Electrical Key Transmitter Sub-assembly

With the brake pedal depressed, hold the electrical key transmitter near the engine switch and check if the power source mode changes.

OK
The power source mode changes.

Tech Tips

If the power source mode changes, the cabin verification is malfunctioning.

Result

Result	Proceed to
The power source mode does not change.	A
The power source mode changes.	B

READ VALUE USING GTS Click here

READ VALUE USING GTS (STOP LIGHT SWITCH 1)

Connect the GTS to the DLC3.
Turn the GTS on.
Enter the following menus: Body Electrical / Power Source Control / Data List.

Read the Data List according to the display on the GTS.

Power Source Control
Tester Display	Measurement Item/Range	Normal Condition	Specified Condition
Stop Light Switch1	State of brake pedal/ON or OFF	ON: Brake pedal depressed OFF: Brake pedal released	Use this item to determine whether the stop light switch is malfunctioning. The engine cannot be started when this item is OFF. When this item is malfunctioning, the engine can be started by pressing and holding the engine switch for a certain period of time.

OK
ON (brake pedal is depressed) and OFF (brake pedal is released) appear on the screen.

Click here

READ VALUE USING GTS

Read the Data List according to the display on the GTS.

Power Source Control
Tester Display	Measurement Item/Range	Normal Condition	Diagnostic Note
Power Supply Condition	Power supply state/IG2 ON, ST ON, All OFF, IG1 ON or ACC ON	ALL OFF: Engine switch off ACC ON: Engine switch on (ACC) (ACC relay on) IG1 ON: Engine switch on (IG) (IG1 relay on) IG2 ON: Engine switch on (IG) (IG2 relay on) ST ON: Sending engine start request signal	Since the IG1 and IG2 relays turn on at approximately the same time, IG1 ON may not be displayed (the IG1 relay turns on for a very short time).

With the engine switch off and brake pedal depressed, hold the electrical key transmitter sub-assembly near the engine switch for 2 seconds or more and read the Data List.

OK

IG2 ON is displayed in the Data List.

Tech Tips

If the entry key function has been canceled on the customization menu, ACC ON is displayed in the Data List.

OK
IG2 ON is displayed in the Data List.

CHECK FOR DTC Click here

CHECK CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)

Read the Data List according to the display on the GTS.

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

Text in Illustration
*a	Component with harness connected (Certification ECU (Smart Key ECU Assembly))	-	-

Read the Data List according to the display on the GTS.

Power Source Control
Tester Display	Measurement Item/Range	Normal Condition	Diagnostic Note
Power Supply Condition	Power supply state/IG2 ON, ST ON, All OFF, IG1 ON or ACC ON	All OFF: Engine switch off (ACC and IG) ACC ON: Engine switch on (ACC) IG1 ON: Engine switch on (IG) (IG1 relay on) IG2 ON: Engine switch on (IG) (IG2 relay on) ST ON: Sending engine start request signal	Since the IG1 and IG2 relays turn on at approximately the same time, IG1 ON may not be displayed (the IG1 relay turns on for a very short time).

Measure the voltage while checking the Data List on the GTS.

Standard Voltage

Tester Connection	Switch Condition	Specified Condition
N93-6 (IG1D) - Body ground	Engine switch off	1 V or less
	Engine switch on (ACC)	1 V or less
	Engine switch on (IG)	9 V or higher
A34-9 (IG2D) - Body ground	Engine switch off	1 V or less
	Engine switch on (ACC)	1 V or less
	Engine switch on (IG)	9 V or higher
N93-4 (ACCD) - Body ground	Engine switch off	1 V or less
	Engine switch on (IG)	8.5 V or higher
	Engine switch on (ACC)	8.5 V or higher

REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)

CHECK RELAY CONTACT SIDE CIRCUIT Click here

READ VALUE USING GTS

Read the Data List according to the display on the GTS.

Power Source Control
Tester Display	Measurement Item/Range	Normal Condition	Diagnostic Note
Start Switch1	Engine switch 1 status/ON or OFF	ON: Engine switch pressed OFF: Engine switch not pressed	If the engine switch is pressed for a short time, the display may not change. Use this item to determine whether the engine switch input signal is malfunctioning.
Start Switch2	Engine switch 2 status/ON or OFF	ON: Engine switch pressed OFF: Engine switch not pressed	Backup for engine switch 1. However, when the engine switch is pressed and held, the control functions only when both engine switch 1 and 2 are normal. Behaves the same way as engine switch 1.

OK
ON (Engine switch is pressed) and OFF (Engine switch is not pressed) appear on the screen.

Result

Result	Proceed to
NG	A
OK	B

GO TO OTHER FLOWCHART (Room Oscillator does not Recognize Key) Click here

INSPECT ENGINE SWITCH

Inspect the engine switch (for 2GR-FSE) Click here.

Inspect the engine switch (for 4GR-FSE) Click here.

Result

Result		Proceed to
OK		A
NG	for 2GR-FSE	B
NG	for 4GR-FSE	C

REPLACE ENGINE SWITCH Click here

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

Disconnect the N93 connector from the certification ECU (smart key ECU assembly).
Disconnect the N43 connector from the engine switch.

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

Standard Resistance

Tester Connection	Condition	Specified Condition
N93-28 (SSW1) - N43-5 (SS1)	Always	Below 1 Ω
N93-30 (SSW2) - N43-1 (SS2)		Below 1 Ω
N93-28 (SSW1) or N43-5 (SS1) - Body ground		10 kΩ or higher
N93-30 (SSW2) or N43-1 (SS2) - Body ground		10 kΩ or higher

REPAIR OR REPLACE HARNESS OR CONNECTOR

REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)

CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) - STOP LIGHT SWITCH ASSEMBLY)

Disconnect the A5 connector from the stop light switch assembly.

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

Standard Resistance

Tester Connection	Condition	Specified Condition
A34-18 (STP1) - A5-2 (L)	Always	Below 1 Ω
A34-18 (STP1) or A5-2 (L)- Body ground	Always	10 kΩ or higher

Text in Illustration

*a
Rear view of wire harness connector

(Certification ECU (Smart Key ECU Assembly))

Reconnect the A5 connector from the stop light switch assembly.

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

Standard Voltage

Tester Connection	Condition	Specified Condition
A34-18 (STP1) - Body ground	Brake pedal released	1 V or less
A34-18 (STP1) - Body ground	Brake pedal depressed	9 V or higher

REPAIR OR REPLACE HARNESS OR CONNECTOR

INSPECT STOP LIGHT SWITCH ASSEMBLY
1. Disconnect the A5 connector from the stop light switch assembly.
2. Inspect the stop light switch assembly Click here.
NG
REPLACE STOP LIGHT SWITCH ASSEMBLY Click here

OK

REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)

CHECK FOR DTC

Enter the following menus: Body Electrical / Entry&Start / Trouble Codes.

Check for DTCs.

Result

Proceed to

The following DTCs are not output:

B2784
B287A

DTC B2784 is output.

DTC B278A is output.

GO TO OTHER FLOWCHART (DTC B2784) Click here

GO TO OTHER FLOWCHART (DTC B278A) Click here

REPLACE ELECTRICAL KEY TRANSMITTER SUB-ASSEMBLY Click here