Last Modified: 05-13-2024 6.11:8.1.0 Doc ID: RM100000001CJ2L
Model Year Start: 2019 Model: Corolla Hatchback Prod Date Range: [06/2018 - 01/2019]
Title: M20A-FKS (ENGINE CONTROL): SFI SYSTEM: Starter Signal Circuit; 2019 MY Corolla Corolla Hatchback [06/2018 - 01/2019]

Starter Signal Circuit

DESCRIPTION

While the engine is being cranked, current flows from terminal STAR of the certification ECU (smart key ECU assembly) to the park/neutral position switch assembly*1 or clutch switch assembly*2 and to terminal STA of the ECM (STA signal).

*1: for Continuously Variable Transaxle Models

*2: for Manual Transaxle Models

WIRING DIAGRAM

Refer to DTC P061512.

Click here 2019 MY Corolla Corolla Hatchback [06/2018 - 01/2019]; M20A-FKS (ENGINE CONTROL): SFI SYSTEM: P061512; Starter Relay Circuit Short to Battery+

CAUTION / NOTICE / HINT

NOTICE:

  • Inspect the fuses for circuits related to this system before performing the following procedure.
  • After turning engine 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 MY Corolla Corolla Hatchback Corolla HV GR Corolla [06/2018 - 01/2019]; INTRODUCTION: REPAIR INSTRUCTION: INITIALIZATION

PROCEDURE

1.

CHECK WHETHER ENGINE CAN BE CRANKED

(a) Check if the engine can be cranked.

Result

Proceed to

Engine cannot be cranked

A

Engine can be cranked

B

B

GO TO STEP 17

A

2.

READ VALUE USING TECHSTREAM (STARTER SW)

(a) Connect the Techstream to the DLC3.

(b) Turn the engine switch on (IG).

(c) Turn the Techstream on.

(d) Enter the following menus: Powertrain / Engine / Data List / Starter SW.

Powertrain > Engine > Data List

Tester Display

Starter SW

(e) Check the value displayed on the Techstream when the engine switch is turned to the on (IG) and START positions.

OK:

Condition

Techstream Display (Starter SW)

Engine switch on (IG)

OFF

Engine started

ON

Result

Proceed to

NG (for Continuously Variable Transaxle Models)

A

NG (for Manual Transaxle Models)

B

OK

C

B

GO TO STEP 6

C

GO TO STEP 9

A

3.

INSPECT PARK/NEUTRAL POSITION SWITCH ASSEMBLY

(a) Inspect the park/neutral position switch assembly.

Click here 2019 - 2025 MY Corolla Corolla Hatchback [06/2018 -        ]; K120 / K121 (CVT): K120 PARK / NEUTRAL POSITION SWITCH: INSPECTION

NG

REPLACE PARK/NEUTRAL POSITION SWITCH ASSEMBLY

OK

4.

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

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

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

(c) Disconnect the ECM connector.

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

O62-2 (STAR) - C62-4 (B)

Always

Below 1 Ω

O62-2 (STAR) - A47-23 (NSW)

Always

Below 1 Ω

O62-2 (STAR), C62-4 (B) or A47-23 (NSW) - Body ground and other terminals

Always

10 kΩ or higher

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

OK

5.

CHECK HARNESS AND CONNECTOR (STA SIGNAL CIRCUIT)

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

(b) Remove the ST relay from the No. 1 engine room relay block and No. 1 junction block assembly.

(c) Disconnect the ECM connector.

(d) Disconnect the TCM connector.

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

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

O62-1 (STA) - 1 (ST relay)

Always

Below 1 Ω

C62-5 (L) - 1 (ST relay)

Always

Below 1 Ω

A47-30 (STA) - 1 (ST relay)

Always

Below 1 Ω

C80-28 (STA) - 1 (ST relay)

Always

Below 1 Ω

O62-1 (STA), 1 (ST relay), C62-5 (L), A47-30 (STA) or C80-28 (STA) - Body ground and other terminals

Always

10 kΩ or higher

OK

GO TO SMART ENTRY AND START SYSTEM

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

6.

INSPECT CLUTCH SWITCH ASSEMBLY

(a) Inspect the clutch switch assembly.

Click here 2019 MY Corolla Corolla Hatchback GR Corolla [06/2018 - 01/2019]; CLUTCH: CLUTCH PEDAL SWITCH: INSPECTION

NG

REPLACE CLUTCH SWITCH ASSEMBLY

OK

7.

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

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

(b) Disconnect the clutch switch assembly connector.

(c) Disconnect the ECM connector.

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

O62-2 (STAR) - A60-2

Always

Below 1 Ω

O62-2 (STAR) - A47-23 (NSW)

Always

Below 1 Ω

O62-2 (STAR), A60-2 or A47-23 (NSW) - Body ground and other terminals

Always

10 kΩ or higher

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

OK

8.

CHECK HARNESS AND CONNECTOR (STA SIGNAL CIRCUIT)

(a) Disconnect the clutch switch assembly connector.

(b) Remove the ST relay from the No. 1 engine room relay block and No. 1 junction block assembly.

(c) Disconnect the ECM connector.

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

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

O62-1 (STA) - 1 (ST relay)

Always

Below 1 Ω

A60-1 - 1 (ST relay)

Always

Below 1 Ω

A47-30 (STA) - 1 (ST relay)

Always

Below 1 Ω

O62-1 (STA), 1 (ST relay), A60-1 or A47-30 (STA) - Body ground and other terminals

Always

10 kΩ or higher

OK

GO TO SMART ENTRY AND START SYSTEM

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

9.

INSPECT ST RELAY

(a) Inspect the ST relay.

Click here 2019 - 2023 MY Corolla Corolla Hatchback [06/2018 - 03/2023]; M20A-FKS (STARTING): RELAY: INSPECTION

NG

REPLACE ST RELAY

OK

10.

INSPECT STARTER ASSEMBLY

(a) Inspect the starter assembly.

Click here 2019 - 2025 MY Corolla Corolla Hatchback [06/2018 -        ]; M20A-FKS (STARTING): STARTER: INSPECTION

NG

REPLACE STARTER ASSEMBLY

OK

11.

CHECK HARNESS AND CONNECTOR (ST RELAY - STARTER ASSEMBLY)

(a) Remove the ST relay from the No. 1 engine room relay block and No. 1 junction block assembly.

(b) Disconnect the starter assembly connector.

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

3 (ST relay) - C82-1 (ST)

Always

Below 1 Ω

3 (ST relay) or C82-1 (ST) - Body ground and other terminals

Always

10 kΩ or higher

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

OK

12.

CHECK TERMINAL VOLTAGE (BATTERY - STARTER ASSEMBLY)

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

(b) Disconnect the cable from the positive (+) battery terminal.

(c) Disconnect the starter assembly connector.

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

Positive (+) battery terminal - C111-1 (B)

Always

Below 1 Ω

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

OK

13.

CHECK TERMINAL VOLTAGE (POWER SOURCE OF ST RELAY)

*1

No. 1 Engine Room Relay Block and No. 1 Junction Block Assembly

*2

ST Relay

(a) Remove the ST relay from the No.1 engine room relay block and No.1 junction block assembly.

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

Standard Voltage:

Tester Connection

Condition

Specified Condition

5 (ST relay) - Body ground

Always

11 to 14 V

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR (BATTERY - ST RELAY)

OK

14.

CHECK HARNESS AND CONNECTOR (ST RELAY - BODY GROUND)

(a) Remove the ST relay from the No.1 engine room relay block and No.1 junction block assembly.

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

2 (ST relay) - Body ground

Always

Below 1 Ω

Result

Proceed to

OK (for Continuously Variable Transaxle Models)

A

OK (for Manual Transaxle Models)

B

NG

C

B

GO TO STEP 16

C

REPAIR OR REPLACE HARNESS OR CONNECTOR

A

15.

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

(a) Remove the ST relay from the No.1 engine room relay block and No.1 junction block assembly.

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

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

1 (ST relay) - O62-5 (L)

Always

Below 1 Ω

OK

PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

16.

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

(a) Remove the ST relay from the No. 1 engine room relay block and No. 1 junction block assembly.

(b) Disconnect the clutch switch assembly connector.

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

1 (ST relay) - A60-1

Always

Below 1 Ω

OK

PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

17.

READ VALUE USING TECHSTREAM (STARTER SW)

(a) Connect the Techstream to the DLC3.

(b) Turn the engine switch on (IG).

(c) Turn the Techstream on.

(d) Enter the following menus: Powertrain / Engine / Data List / Starter SW.

Powertrain > Engine > Data List

Tester Display

Starter SW

(e) Check the value displayed on the Techstream when the engine switch is turned to the on (IG) and START positions.

OK:

Condition

Techstream Display (Starter SW)

Engine switch on (IG)

OFF

Engine started

ON

OK

PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR (ST RELAY - ECM)