THEFT DETERRENT / KEYLESS ENTRY: SMART KEY SYSTEM (for Start Function, Gasoline Model): Engine does not Start; 2023 - 2025 MY Corolla Corolla Hatchback GR Corolla [03/2023

Last Modified: 05-13-2024	6.11:8.1.0	Doc ID: RM100000002BENP
Model Year Start: 2023	Model: GR Corolla	Prod Date Range: [03/2023 - ]
Title: THEFT DETERRENT / KEYLESS ENTRY: SMART KEY SYSTEM (for Start Function, Gasoline Model): Engine does not Start; 2023 - 2025 MY Corolla Corolla Hatchback GR Corolla [03/2023 - ]

Engine does not Start

DESCRIPTION

except Manual Transaxle

When the electrical key transmitter sub-assembly is in the cabin and the engine switch is pressed, the certification ECU (smart key ECU assembly) receives a signal and changes the power source mode. Additionally, when the shift position is in P and the brake pedal is depressed, the engine can be started by pressing the engine switch. If the steering is unlocked, the engine can also be started by pressing the engine switch with the shift position in N and the brake pedal depressed.

Related Data List and Active Test Items

Problem Symptom	Data List and Active Test
Engine does not start	Power Source Control Stop Light Switch Shift P Signal Neutral SW/ Clutch SW* Starter Relay Driving Request (Starting Control) Starter Relay Power Supply Condition Smart Key Immobiliser Start Request L Code Check S Code Check

*: for M20A-FKS (except K121 CVT)

for Manual Transaxle

Related Data List and Active Test Items

Problem Symptom	Data List and Active Test
Engine does not start	Power Source Control Neutral SW/ Clutch SW Starter Relay Driving Request (Starting Control) Starter Relay Power Supply Condition Smart Key Immobiliser Start Request L Code Check S Code Check

WIRING DIAGRAM

except K121 CVT

for K121 CVT

CAUTION / NOTICE / HINT

NOTICE:

When using the GTS with the ignition switch off, connect the GTS to the DLC3 and turn a courtesy light switch on and off at intervals of 1.5 seconds or less until communication between the GTS and the vehicle begins.
Then select Model Code "KEY REGIST" under manual mode and enter the following menus: Body Electrical / Start Key(CAN). While using the GTS, periodically turn a courtesy light switch on and off at intervals of 1.5 seconds or less to maintain communication between the GTS and the vehicle.
The smart key system (for Start Function) uses the LIN communication system and CAN communication system. Inspect the communication function by following How to Proceed with Troubleshooting. Troubleshoot the smart key system (for Start Function) after confirming that the communication systems are functioning properly.
Click here
If the smart key system (for Start Function) has been disabled, enable the system before performing troubleshooting.
Click here
Inspect the fuses of circuits related to this system before performing the following procedure.
Before replacing the certification ECU (smart key ECU assembly) or an electrical key transmitter sub-assembly, refer to Registration.
Click here
After completing repairs, confirm that the problem does not recur.
After performing repairs, confirm that no DTCs are output by performing "DTC Output Confirmation Operation."

HINT:

If the ignition switch is changed from ON to ACC with the shift position in any position other than P, and then the shift position is moved to P and the engine switch is pressed with the brake pedal depressed, the ignition switch will turn off.*
If the brake pedal is repeatedly depressed while the engine is stopped, the brake booster pressure will be released and the force required to depress the brake pedal to illuminate the stop lights will increase.*
- *: except Manual Transaxle

PROCEDURE

1.	CHECK WHETHER ENGINE STARTS

(a) Using an electrical key transmitter sub-assembly which is registered to the vehicle, turn the ignition switch to ON.

(b) Check that the engine can be started 5 seconds after the ignition switch turned to ON.

OK:

Engine starts normally.

CHECK VEHICLE CONTROL HISTORY (ROB)

2.	CHECK SECURITY INDICATOR LIGHT (IMMOBILISER FUNCTION UNSET)

(a) Get into the vehicle while carrying an electrical key transmitter sub-assembly.

(b) Move the shift position to P.*1

(c) Press the engine switch with the brake pedal released and check that the security indicator light changes from blinking to off at the same time that the power source mode changes to ACC.*1

(d) Press the engine switch with the clutch pedal released and check that the security indicator light changes from blinking to off at the same time that the power source mode changes to ACC.*2

OK:

The security indicator light changes from blinking to off at the same time that the power source mode changes to ACC.

HINT:

The immobiliser function can be determined to be operating correctly if the security indicator light changes from blinking to off at the same time that the power source mode changes to ACC.

*1: except Manual Transaxle
*2: for Manual Transaxle

GO TO OTHER PROBLEM (Immobiliser System does not Operate Properly)

3.	CHECK FOR DTC

(a) Using the GTS, check if LIN communication DTC B278588 and B278987 are output.

Body Electrical > Smart Key > Trouble Codes

OK:

DTC B278588 and B278987 are not output.

GO TO LIN COMMUNICATION SYSTEM (DTC B278588)

4.	CHECK ENGINE CRANKING OPERATION

(a) Get into the vehicle while carrying an electrical key transmitter sub-assembly.

(b) Move the shift position to P.*1

(d) Depressed the clutch pedal.*2

*1: except Manual Transaxle
*2: for Manual Transaxle

(e) Check that the key indicator display is displayed on the multi-information display in the combination meter assembly, and then press the engine switch and check that the engine cranks.

Result	Proceed to
Engine cranks and initial combustion occurs	A
Engine cranks but initial combustion does not occur	B
Engine does not crank	C

GO TO OTHER PROBLEM (Immobiliser System does not Operate Properly)

GO TO SFI SYSTEM

for M20A-FKS: Click here

for G16E-GTS: Click here

5.	CHECK ENGINE SWITCH CONDITION

(a) Get into the vehicle while carrying an electrical key transmitter sub-assembly.

(b) Move the shift position to P.*1

(d) With the clutch pedal released, check that pressing the engine switch causes the power source mode to change.*2

*1: except Manual Transaxle
*2: for Manual Transaxle

Result	Proceed to
Power source mode changes : Off → ACC → ON → off (except Manual Transaxle (except K121 CVT))	A
Power source mode changes : Off → ACC → ON → off (for Manual Transaxle)	B
Power source mode changes : Off → ACC → ON → off (except Manual Transaxle (for K121 CVT))	C
Power source mode does not change to ACC or ON	D
Power source mode changes to ON but not to ACC	E
Power source mode changes to ACC but not to ON	F

GO TO STEP 28

GO TO STEP 41

GO TO OTHER PROBLEM (Power Source Mode does not Change to ON (IG and ACC))

GO TO OTHER PROBLEM (Power Source Mode does not Change to ON (ACC))

GO TO OTHER PROBLEM (Power Source Mode does not Change to ON (IG))

6.	READ VALUE USING GTS (STOP LIGHT SWITCH1)

(a) Read the Data List according to the display on the GTS.

Body Electrical > Power Source Control > Data List

Tester Display

Measurement Item

Range

Normal Condition

Diagnostic Note

Stop Light Switch

State of brake pedal

OFF or ON

OFF: Brake pedal released

ON: Brake pedal depressed

Use this item to determine if the stop light switch assembly is malfunctioning.
The engine cannot be started when this item is OFF.
If the stop light switch assembly is malfunctioning, the engine can be started by pressing and holding the engine switch for a certain period of time.

Body Electrical > Power Source Control > Data List

Tester Display
Stop Light Switch

OK:

The GTS display changes correctly in response to the brake pedal operation.

GO TO STEP 25

7.	READ VALUE USING GTS (SHIFT P SIGNAL)

(a) Move the shift position to P.

(b) Read the Data List according to the display on the GTS.

Body Electrical > Power Source Control > Data List

Tester Display

Measurement Item

Range

Normal Condition

Diagnostic Note

Shift P Signal

Shift position P

OFF or ON

OFF: Shift position not in P

ON: Shift position in P

Use this item to determine if the shift position switch is malfunctioning.
The engine cannot be started when this item is OFF.

Body Electrical > Power Source Control > Data List

Tester Display
Shift P Signal

OK:

ON is displayed on the GTS.

GO TO STEP 23

8.	READ VALUE USING GTS (NEUTRAL SW/ CLUTCH SW, SHIFT P/N (STARTING CONTROL))

(a) Read the Data List according to the display on the GTS.

Body Electrical > Power Source Control > Data List

Tester Display

Measurement Item

Range

Normal Condition

Diagnostic Note

Neutral Switch / Clutch Switch

Shift position (P and N)

OFF or ON

OFF: Shift position in any position other than P or N

ON: Shift position in P or N

Use this item to determine if the park/neutral position switch assembly is malfunctioning.
When the engine cannot be started due to a park/neutral position switch assembly malfunction, OFF is displayed.

Body Electrical > Power Source Control > Data List

Tester Display
Neutral Switch / Clutch Switch

Body Electrical > Power Source Control > Data List

Tester Display

Measurement Item

Range

Normal Condition

Diagnostic Note

Shift P/N (Starting Control)

Park/Neutral position switch status

OFF or ON

OFF: Shift position in any position other than P or N

ON: Shift position in P or N

When OFF is displayed, the engine will not crank.

Body Electrical > Power Source Control > Data List

Tester Display
Shift P/N (Starting Control)

OK:

The GTS display changes correctly in response to the shift position.

GO TO STEP 18

9.	READ VALUE USING GTS (POWER SUPPLY CONDITION)

(a) Read the Data List according to the display on the GTS.

Body Electrical > Power Source Control > Data List

Tester Display

Measurement Item

Range

Normal Condition

Diagnostic Note

Power Supply Condition

Power supply state

OFF, ACC ON, IGR ON, IGP ON or Starter ON

OFF: Ignition switch off

ACC ON: Ignition switch ACC

IGR ON: Ignition switch ON

IGP ON: Ignition switch ON

Starter ON: Sending engine start request signal

Body Electrical > Power Source Control > Data List

Tester Display
Power Supply Condition

NOTICE:

Check that the key indicator display is displayed on the multi-information display in the combination meter assembly, and then press the engine switch.

OK:

The GTS display changes correctly in response to the engine switch operation.

GO TO STEP 17

10.	READ VALUE USING GTS (STARTER RELAY DRIVING REQUEST (STARTING CONTROL))

(a) Get into the vehicle while carrying an electrical key transmitter sub-assembly.

(b) Move the shift position to P.

(c) According to the display on the GTS, read the Data List while pressing the engine switch with the brake pedal depressed.

Body Electrical > Power Source Control > Data List

Tester Display

Measurement Item

Range

Normal Condition

Diagnostic Note

Starter Relay Driving Request (Starting Control)

Engine start request signal status

OFF or ON

OFF: The engine switch is not pressed

ON: With the shift position in P and the brake pedal depressed, the engine switch is pressed and held

When the engine cannot be started due to a start request signal malfunction, OFF is displayed.
When the engine switch is pressed, the duration of time that ON is displayed will be extremely short. As such, the engine switch needs to be pressed and held for a certain period of time.

Body Electrical > Power Source Control > Data List

Tester Display
Starter Relay Driving Request (Starting Control)

OK:

The GTS display changes.

REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)

11.	CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) - ST RELAY)

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

Standard Voltage:

Tester Connection	Condition	Specified Condition
No. 1 engine room relay block and No. 1 junction block assembly ST relay terminal 1 - Body ground	Engine switch pressed and held with brake pedal depressed (starter on) → Approximately 1 second after engine switch released (starter off)	6 V or higher* → 1.0 V or less

HINT:

*: While the engine is cranking, the auxiliary battery voltage may drop to approximately 6 V.

*1	No. 1 Engine Room Relay Block and No. 1 Junction Block Assembly (ST Relay Holder)

GO TO STEP 16

12.	CHECK HARNESS AND CONNECTOR (ST RELAY - AUXILIARY BATTERY AND BODY GROUND)

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

Standard Resistance:

Tester Connection	Condition	Specified Condition
No. 1 engine room relay block and No. 1 junction block assembly ST relay terminal 2 - Body ground	Always	Below 1 Ω

*1	No. 1 Engine Room Relay Block and No. 1 Junction Block Assembly (ST Relay Holder)

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

Standard Voltage:

Tester Connection	Condition	Specified Condition
No. 1 engine room relay block and No. 1 junction block assembly ST relay terminal 5 - Body ground	Always	11 to 14 V

REPAIR OR REPLACE HARNESS OR CONNECTOR

13.	INSPECT ST RELAY

Click here

REPLACE ST RELAY

14.	CHECK HARNESS AND CONNECTOR (STARTER ASSEMBLY - ST RELAY)

(a) Disconnect the C82 starter assembly connector.

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

Standard Resistance:

Tester Connection	Condition	Specified Condition
No. 1 engine room relay block and No. 1 junction block assembly ST relay terminal 3 - C82-1 (ST)	Always	Below 1 Ω
No. 1 engine room relay block and No. 1 junction block assembly ST relay terminal 3 or C82-1 (ST) - Other terminals and body ground	Always	10 kΩ or higher

REPAIR OR REPLACE HARNESS OR CONNECTOR

15.	CHECK HARNESS AND CONNECTOR (STARTER ASSEMBLY - AUXILIARY BATTERY)

(a) Disconnect the C111 starter assembly connector.

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

Standard Voltage:

Tester Connection	Condition	Specified Condition
C111-1 (B) - Body ground	Always	11 to 14 V

REPLACE STARTER ASSEMBLY

for M20A-FKS: Click here

for G16E-GTS: Click here

REPAIR OR REPLACE HARNESS OR CONNECTOR

16.	CHECK HARNESS AND CONNECTOR (PARK/NEUTRAL POSITION SWITCH ASSEMBLY - ST RELAY)

(a) Disconnect the C62 park/neutral position switch assembly connector.

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

Standard Resistance:

Tester Connection	Condition	Specified Condition
C62-5 (L) - No. 1 engine room relay block and No. 1 junction block assembly ST relay terminal 1	Always	Below 1 Ω
C62-5 (L) or No. 1 engine room relay block and No. 1 junction block assembly ST relay terminal 1 - Other terminals and body ground	Always	10 kΩ or higher

REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)

REPAIR OR REPLACE HARNESS OR CONNECTOR

17.	CHECK SECURITY INDICATOR LIGHT (IMMOBILISER FUNCTION UNSET)

(a) Get into the vehicle while carrying an electrical key transmitter sub-assembly.

(b) Move the shift lever to P.

(c) Press the engine switch with the brake pedal released and check that the security indicator light changes from blinking to off at the same time that the power source mode changes to ACC.

OK:

The security indicator light changes from blinking to off at the same time that the power source mode changes to ACC.

HINT:

The immobiliser function can be determined to be operating correctly if the security indicator light changes from blinking to off at the same time that the power source mode changes to ACC.

REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)

GO TO OTHER PROBLEM (Immobiliser System does not Operate Properly)

18.	READ VALUE USING GTS (NEUTRAL SW/ CLUTCH SW)

(a) Disconnect the A47 ECM connector.

(b) Read the Data List according to the display on the GTS.

Body Electrical > Power Source Control > Data List

Tester Display

Measurement Item

Range

Normal Condition

Diagnostic Note

Neutral Switch / Clutch Switch

Shift position (P and N)

OFF or ON

OFF: Shift position in any position other than P or N

ON: Shift position in P or N

Use this item to determine if the park/neutral position switch assembly is malfunctioning.
When the engine cannot be started due to a park/neutral position switch assembly malfunction, OFF is displayed.

Body Electrical > Power Source Control > Data List

Tester Display
Neutral Switch / Clutch Switch

OK:

The GTS display changes correctly in response to the shift position.

REPLACE ECM

19.	INSPECT PARK/NEUTRAL POSITION SWITCH ASSEMBLY

Click here

REPLACE PARK/NEUTRAL POSITION SWITCH ASSEMBLY

20.	CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) - PARK/NEUTRAL POSITION SWITCH ASSEMBLY)

(a) Disconnect the O175 certification ECU (smart key ECU assembly) connector.

(b) Disconnect the C62 park/neutral position switch assembly connector.

(d) Remove the ST relay.

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

Standard Resistance:

Tester Connection	Condition	Specified Condition
O175-3 (STA) - C62-5 (L)	Always	Below 1 Ω
O175-3 (STA) - A47-30 (STA)	Always	Below 1 Ω
O175-3 (STA) - No. 1 engine room relay block and No. 1 junction block assembly ST relay terminal 1	Always	Below 1 Ω
O175-10 (STAR) - C62-4 (B)	Always	Below 1 Ω
O175-10 (STAR) - A47-23 (NSW)	Always	Below 1 Ω
O175-3 (STA), C62-5 (L), A47-30 (STA) or No. 1 engine room relay block and No. 1 junction block assembly ST relay terminal 1 - Other terminals and body ground	Always	10 kΩ or higher
O175-10 (STAR), C62-4 (B) or A47-23 (NSW) - Other terminals and body ground	Always	10 kΩ or higher

REPAIR OR REPLACE HARNESS OR CONNECTOR

21.	CHECK CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)

(a) Connect the O175 certification ECU (smart key ECU assembly) connector.

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

Standard Voltage:

Tester Connection	Condition	Specified Condition
O175-10 (STAR) - Body ground	Engine switch pressed and held with brake pedal depressed (starter on) → Approximately 1 second after engine switch released (starter off)	6 V or higher* → 1.0 V or less

HINT:

*: While the engine is cranking, the auxiliary battery voltage may drop to approximately 6 V.

REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)

22.	INSPECT ST RELAY

for M20A-FKS: Click here

for G16E-GTS: Click here

REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)

REPLACE ST RELAY

for M20A-FKS: Click here

for G16E-GTS: Click here

23.	CHECK SHIFT LOCK CONTROL UNIT ASSEMBLY

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

Standard Resistance:

Tester Connection	Condition	Specified Condition
I167-14 (P) - Body ground	Shift position in P → Shift position not in P	30 kΩ or higher → Below 200 Ω

REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)

24.	CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) - SHIFT LOCK CONTROL UNIT ASSEMBLY)

(a) Disconnect the I167 certification ECU (smart key ECU assembly) connector.

(b) Disconnect the I17 shift lock control unit assembly connector.

Standard Resistance:

Tester Connection	Condition	Specified Condition
I167-14 (P) - I17-3 (P2)	Always	Below 1 Ω
I167-14 (P) or I17-3 (P2) - Other terminals and body ground	Always	10 kΩ or higher

REPLACE SHIFT LOCK CONTROL UNIT ASSEMBLY

REPAIR OR REPLACE HARNESS OR CONNECTOR

25.	CHECK HARNESS AND CONNECTOR (STOP LIGHT SWITCH ASSEMBLY - AUXILIARY BATTERY AND GROUND)

(a) Disconnect the A53 stop light switch assembly connector.

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

Standard Voltage:

Tester Connection	Condition	Specified Condition
A53-7 (B) - Body ground	Always	11 to 14 V

*a	Front view of wire harness connector (to Stop Light Switch Assembly)

Standard Resistance:

Tester Connection	Condition	Specified Condition
A53-2 (GND) - Body ground	Always	Below 1 Ω

REPAIR OR REPLACE HARNESS OR CONNECTOR

26.	INSPECT STOP LIGHT SWITCH ASSEMBLY

Click here

REPLACE STOP LIGHT SWITCH ASSEMBLY

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

(a) Disconnect the O175 certification ECU (smart key ECU assembly) connector.

(b) Disconnect the A47 ECM connector.

(d) Disconnect the I17 shift lock control unit assembly connector.

(e) Disconnect the C80 TCM connector.

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

Standard Resistance:

Tester Connection	Condition	Specified Condition
O175-21 (STP1) - A53-3 (L)	Always	Below 1 Ω
O175-21 (STP1) or A53-3 (L) - Other terminals and body ground	Always	10 kΩ or higher

REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)

REPAIR OR REPLACE HARNESS OR CONNECTOR

28.	READ VALUE USING GTS (NEUTRAL SWITCH / CLUTCH SWITCH)

(a) Read the Data List according to the display on the GTS.

Body Electrical > Power Source Control > Data List

Tester Display

Measurement Item

Range

Normal Condition

Diagnostic Note

Neutral Switch / Clutch Switch

State of clutch pedal

OFF or ON

OFF: Clutch pedal released

ON: Clutch pedal depressed

Use this item to help determine if the clutch position switch is malfunctioning.
The engine cannot be started when this item is "OFF".

Body Electrical > Power Source Control > Data List

Tester Display
Neutral Switch / Clutch Switch

OK:

The GTS display changes correctly in response to the clutch pedal operation.

GO TO STEP 38

29.	READ VALUE USING GTS (POWER SUPPLY CONDITION)

(a) Read the Data List according to the display on the GTS.

Body Electrical > Power Source Control > Data List

Tester Display

Measurement Item

Range

Normal Condition

Diagnostic Note

Power Supply Condition

Power supply state

OFF, ACC ON, IGR ON, IGP ON or Starter ON

OFF: Ignition switch off

ACC ON: Ignition switch ACC

IGR ON: Ignition switch ON

IGP ON: Ignition switch ON

Starter ON: Sending engine start request signal

Body Electrical > Power Source Control > Data List

Tester Display
Power Supply Condition

NOTICE:

Check that the key indicator display is displayed on the multi-information display in the combination meter assembly, and then press the engine switch.

OK:

The GTS display changes correctly in response to the engine switch operation.

GO TO STEP 37

30.	READ VALUE USING GTS (STARTER RELAY DRIVING REQUEST (STARTING CONTROL))

(a) Get into the vehicle while carrying an electrical key transmitter sub-assembly.

(b) Move the shift position to P.

(c) According to the display on the GTS, read the Data List while pressing the engine switch with the clutch pedal depressed.

Body Electrical > Power Source Control > Data List

Tester Display

Measurement Item

Range

Normal Condition

Diagnostic Note

Starter Relay Driving Request (Starting Control)

Engine start request signal status

OFF or ON

OFF: The engine switch is not pressed

ON: With the clutch pedal depressed, the engine switch is pressed and held

When the engine cannot be started due to a start request signal malfunction, OFF is displayed.
When the engine switch is pressed, the duration of time that ON is displayed will be extremely short. As such, the engine switch needs to be pressed and held for a certain period of time.

Body Electrical > Power Source Control > Data List

Tester Display
Starter Relay Driving Request (Starting Control)

OK:

The GTS display changes.

REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)

31.	CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) - ST RELAY)

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

Standard Voltage:

Tester Connection	Condition	Specified Condition
No. 1 engine room relay block and No. 1 junction block assembly ST relay terminal 2 - Body ground	Engine switch pressed and held with clutch pedal depressed (starter on) → Approximately 1 second after engine switch released (starter off)	6 V or higher* → 1.0 V or less

HINT:

*: While the engine is cranking, the auxiliary battery voltage may drop to approximately 6 V.

*1	No. 1 Engine Room Relay Block and No. 1 Junction Block Assembly (ST Relay Holder)

GO TO STEP 36

32.	CHECK HARNESS AND CONNECTOR (ST RELAY - AUXILIARY BATTERY AND BODY GROUND)

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

Standard Resistance:

Tester Connection	Condition	Specified Condition
No. 1 engine room relay block and No. 1 junction block assembly ST relay terminal 1 - Body ground	Always	Below 1 Ω

*1	No. 1 Engine Room Relay Block and No. 1 Junction Block Assembly (ST Relay Holder)

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

Standard Voltage:

Tester Connection	Condition	Specified Condition
No. 1 engine room relay block and No. 1 junction block assembly ST relay terminal 5 - Body ground	Always	11 to 14 V

REPAIR OR REPLACE HARNESS OR CONNECTOR

33.	INSPECT ST RELAY

Click here

REPLACE ST RELAY

34.	CHECK HARNESS AND CONNECTOR (STARTER ASSEMBLY - ST RELAY)

(a) Disconnect the C82 starter assembly connector.

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

Standard Resistance:

Tester Connection	Condition	Specified Condition
No. 1 engine room relay block and No. 1 junction block assembly ST relay terminal 3 - C82-1 (ST)	Always	Below 1 Ω
No. 1 engine room relay block and No. 1 junction block assembly ST relay terminal 3 or C82-1 (ST) - Other terminals and body ground	Always	10 kΩ or higher

REPAIR OR REPLACE HARNESS OR CONNECTOR

35.	CHECK HARNESS AND CONNECTOR (STARTER ASSEMBLY - AUXILIARY BATTERY)

(a) Disconnect the C111 starter assembly connector.

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

Standard Voltage:

Tester Connection	Condition	Specified Condition
C111-1 (B) - Body ground	Always	11 to 14 V

REPLACE STARTER ASSEMBLY

REPAIR OR REPLACE HARNESS OR CONNECTOR

36.	CHECK HARNESS AND CONNECTOR (CLUTCH SWITCH ASSEMBLY - ST RELAY)

(a) Disconnect the A60 clutch switch assembly connector.

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

Standard Resistance:

Tester Connection	Condition	Specified Condition
A60-1 - No. 1 engine room relay block and No. 1 junction block assembly ST relay terminal 2	Always	Below 1 Ω
A60-1 or No. 1 engine room relay block and No. 1 junction block assembly ST relay terminal 2 - Other terminals and body ground	Always	10 kΩ or higher

REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)

REPAIR OR REPLACE HARNESS OR CONNECTOR

37.	CHECK STEERING LOCK FUNCTION

(a) Check that the steering unlocks when the ignition switch is turned to ACC.

OK:

The steering unlocks.

REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)

GO TO OTHER PROBLEM (Unable to Unlock Steering Wheel (Engine cannot Start))

38.	READ VALUE USING GTS (NEUTRAL SW/ CLUTCH SW)

(a) Disconnect the A139 ECM connector.

(b) Read the Data List according to the display on the GTS.

Body Electrical > Power Source Control > Data List

Tester Display

Measurement Item

Range

Normal Condition

Diagnostic Note

Neutral Switch / Clutch Switch

State of clutch pedal

OFF or ON

OFF: Clutch pedal released

ON: Clutch pedal depressed

Use this item to help determine if the clutch position switch is malfunctioning.
The engine cannot be started when this item is "OFF".

Body Electrical > Power Source Control > Data List

Tester Display
Neutral Switch / Clutch Switch

OK:

The GTS display changes correctly in response to the shift position.

REPLACE ECM

39.	INSPECT CLUTCH SWITCH ASSEMBLY

Click here

REPLACE CLUTCH SWITCH ASSEMBLY

40.	CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) - CLUTCH SWITCH ASSEMBLY)

(a) Disconnect the O175 certification ECU (smart key ECU assembly) connector.

(b) Disconnect the A139 ECM connector.

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

Standard Resistance:

Tester Connection	Condition	Specified Condition
O175-10 (STAR) - A60-2	Always	Below 1 Ω
O175-10 (STAR) - O139-23 (NSW)	Always	Below 1 Ω
O175-3 (STA) - A60-1	Always	Below 1 Ω
O175-3 (STA) - O139-30 (STA)	Always	Below 1 Ω
O175-3 (STA) - No. 1 engine room relay block and No. 1 junction block assembly ST relay terminal 2	Always	Below 1 Ω
O175-10 (STAR), A60-2 or O139-23 (NSW) - Other terminals and body ground	Always	Below 1 Ω
O175-3 (STA), A60-1, O139-30 (STA) or No. 1 engine room relay block and No. 1 junction block assembly ST relay terminal 2 - Other terminals and body ground	Always	10 kΩ or higher

REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)

REPAIR OR REPLACE HARNESS OR CONNECTOR

41.	READ VALUE USING GTS (STOP LIGHT SWITCH1)

(a) Read the Data List according to the display on the GTS.

Body Electrical > Power Source Control > Data List

Tester Display

Measurement Item

Range

Normal Condition

Diagnostic Note

Stop Light Switch

State of brake pedal

OFF or ON

OFF: Brake pedal released

ON: Brake pedal depressed

Use this item to determine if the stop light switch assembly is malfunctioning.
The engine cannot be started when this item is OFF.
If the stop light switch assembly is malfunctioning, the engine can be started by pressing and holding the engine switch for a certain period of time.

Body Electrical > Power Source Control > Data List

Tester Display
Stop Light Switch

OK:

The GTS display changes correctly in response to the brake pedal operation.

GO TO STEP 56

42.	READ VALUE USING GTS (SHIFT P SIGNAL)

(a) Move the shift position to P.

(b) Read the Data List according to the display on the GTS.

Body Electrical > Power Source Control > Data List

Tester Display

Measurement Item

Range

Normal Condition

Diagnostic Note

Shift P Signal

Shift position P

OFF or ON

OFF: Shift position not in P

ON: Shift position in P

Use this item to determine if the shift position switch is malfunctioning.
The engine cannot be started when this item is OFF.

Body Electrical > Power Source Control > Data List

Tester Display
Shift P Signal

OK:

ON is displayed on the GTS.

GO TO STEP 54

43.	READ VALUE USING GTS (POWER SUPPLY CONDITION)

(a) Read the Data List according to the display on the GTS.

Body Electrical > Power Source Control > Data List

Tester Display

Measurement Item

Range

Normal Condition

Diagnostic Note

Power Supply Condition

Power supply state

OFF, ACC ON, IGR ON, IGP ON or Starter ON

OFF: Ignition switch off

ACC ON: Ignition switch ACC

IGR ON: Ignition switch ON

IGP ON: Ignition switch ON

Starter ON: Sending engine start request signal

Body Electrical > Power Source Control > Data List

Tester Display
Power Supply Condition

NOTICE:

Check that the key indicator display is displayed on the multi-information display in the combination meter assembly, and then press the engine switch.

OK:

The GTS display changes correctly in response to the engine switch operation.

GO TO STEP 53

44.	INSPECT ECM (PPOS TERMINAL)

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

Standard Voltage:

Tester Connection	Condition	Specified Condition
O175-3 (STA) - Body ground	Shift lever in P/N → Shift lever not in P/N	11 to 14 V → 1.0 V or less

GO TO STEP 52

45.	INSPECT ST RELAY

Click here

REPLACE ST RELAY

46.	CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) - ST RELAY)

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

Standard Voltage:

Tester Connection	Condition	Specified Condition
No. 1 engine room relay block and No. 1 junction block assembly ST relay terminal 1 - Body ground	Engine switch pressed and held with brake pedal depressed (starter on) → Approximately 1 second after engine switch released (starter off)	6 V or higher* → 1.0 V or less

HINT:

*: While the engine is cranking, the auxiliary battery voltage may drop to approximately 6 V.

*1	No. 1 Engine Room Relay Block and No. 1 Junction Block Assembly (ST NO. 1 Relay Holder)

GO TO STEP 50

47.	CHECK HARNESS AND CONNECTOR (ST RELAY - AUXILIARY BATTERY AND GROUND)

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

Standard Resistance:

Tester Connection	Condition	Specified Condition
No. 1 engine room relay block and No. 1 junction block assembly ST relay terminal 2 - Body ground	Always	Below 1 Ω

*1	No. 1 Engine Room Relay Block and No. 1 Junction Block Assembly (ST Relay Holder)

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

Standard Voltage:

Tester Connection	Condition	Specified Condition
No. 1 engine room relay block and No. 1 junction block assembly ST relay terminal 5 - Body ground	Always	11 to 14 V

REPAIR OR REPLACE HARNESS OR CONNECTOR

48.	CHECK HARNESS AND CONNECTOR (STARTER ASSEMBLY - ST RELAY)

(a) Disconnect the C82 starter assembly connector.

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

Standard Resistance:

Tester Connection	Condition	Specified Condition
No. 1 engine room relay block and No. 1 junction block assembly ST relay terminal 3 - C82-1 (ST)	Always	Below 1 Ω
No. 1 engine room relay block and No. 1 junction block assembly ST relay terminal 3 or C82-1 (ST) - Other terminals and body ground	Always	10 kΩ or higher

REPAIR OR REPLACE HARNESS OR CONNECTOR

49.	CHECK HARNESS AND CONNECTOR (STARTER ASSEMBLY - AUXILIARY BATTERY)

(a) Disconnect the C111 starter assembly connector.

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

Standard Voltage:

Tester Connection	Condition	Specified Condition
C111-1 (B) - Body ground	Always	11 to 14 V

REPLACE STARTER ASSEMBLY

REPAIR OR REPLACE HARNESS OR CONNECTOR

50.	INSPECT CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)

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

Standard Voltage:

Tester Connection	Condition	Specified Condition
O175-10 (STAR) - Body ground	Engine switch pressed and held with brake pedal depressed (starter on) → Approximately 1 second after engine switch released (starter off)	6 V or higher* → 1.0 V or less

HINT:

*: While the engine is cranking, the auxiliary battery voltage may drop to approximately 6 V.

REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)

51.	CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) - ST NO. 1 RELAY)

(a) Disconnect the O175 certification ECU (smart key ECU assembly) connector.

(b) Disconnect the A178 ECM connector.

Standard Resistance:

Tester Connection	Condition	Specified Condition
O175-10 (STAR) - No. 1 engine room relay block and No. 1 junction block assembly ST relay terminal 1	Always	Below 1 Ω
O175-10 (STAR) - A178-18 (STA)	Always	Below 1 Ω
O175-10 (STAR), A178-18 (STA) or No. 1 engine room relay block and No. 1 junction block assembly ST relay terminal 1 - Other terminals and body ground	Always	10 kΩ or higher

REPLACE ECM

REPAIR OR REPLACE HARNESS OR CONNECTOR

52.	CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) - ECM)

(a) Disconnect the O175 certification ECU (smart key ECU assembly) connector.

(b) Disconnect the A178 ECM connector.

Standard Resistance:

Tester Connection	Condition	Specified Condition
O175-3 (STA) - A178-81 (PPOS)	Always	Below 1 Ω
O175-3 (STA) or A178-81 (PPOS) - Other terminals and body ground	Always	10 kΩ or higher

REPLACE ECM

REPAIR OR REPLACE HARNESS OR CONNECTOR

53.	CHECK SECURITY INDICATOR LIGHT (IMMOBILISER FUNCTION UNSET)

(a) Get into the vehicle while carrying an electrical key transmitter sub-assembly.

(b) Move the shift lever to P.

(c) Press the engine switch with the brake pedal released and check that the security indicator light changes from blinking to off at the same time that the power source mode changes to ACC.

OK:

The security indicator light changes from blinking to off at the same time that the power source mode changes to ACC.

HINT:

The immobiliser function can be determined to be operating correctly if the security indicator light changes from blinking to off at the same time that the power source mode changes to ACC.

REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)

GO TO OTHER PROBLEM (Immobiliser System does not Operate Properly)

54.	CHECK SHIFT LOCK CONTROL UNIT ASSEMBLY

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

Standard Resistance:

Tester Connection	Condition	Specified Condition
I167-14 (P) - Body ground	Shift position in P → Shift position not in P	30 kΩ or higher → Below 200 Ω

REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)

55.	CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) - SHIFT LOCK CONTROL UNIT ASSEMBLY)

(a) Disconnect the I167 certification ECU (smart key ECU assembly) connector.

(b) Disconnect the I17 shift lock control unit assembly connector.

Standard Resistance:

Tester Connection	Condition	Specified Condition
I167-14 (P) - I17-3 (P2)	Always	Below 1 Ω
I167-14 (P) or I17-3 (P2) - Other terminals and body ground	Always	10 kΩ or higher

REPLACE SHIFT LOCK CONTROL UNIT ASSEMBLY

REPAIR OR REPLACE HARNESS OR CONNECTOR

56.	CHECK HARNESS AND CONNECTOR (STOP LIGHT SWITCH ASSEMBLY - AUXILIARY BATTERY AND GROUND)

(a) Disconnect the A53 stop light switch assembly connector.

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

Standard Voltage:

Tester Connection	Condition	Specified Condition
A53-7 (B) - Body ground	Always	11 to 14 V

*a	Front view of wire harness connector (to Stop Light Switch Assembly)

Standard Resistance:

Tester Connection	Condition	Specified Condition
A53-2 (GND) - Body ground	Always	Below 1 Ω

REPAIR OR REPLACE HARNESS OR CONNECTOR

57.	INSPECT STOP LIGHT SWITCH ASSEMBLY

Click here

REPLACE STOP LIGHT SWITCH ASSEMBLY

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

(a) Disconnect the O175 certification ECU (smart key ECU assembly) connector.

(b) Disconnect the A178 ECM connector.

(d) Disconnect the I17 shift lock control unit assembly connector.

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

Standard Resistance:

Tester Connection	Condition	Specified Condition
O175-21 (STP1) - A53-3 (L)	Always	Below 1 Ω
O175-21 (STP1) or A53-3 (L) - Other terminals and body ground	Always	10 kΩ or higher

REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)

REPAIR OR REPLACE HARNESS OR CONNECTOR