Cranking Holding Function Circuit 1GR-FE

DESCRIPTION

WIRING DIAGRAM

INSPECTION PROCEDURE

CHECK CRANKING

READ VALUE USING INTELLIGENT TESTER (STARTER SIGNAL)

INSPECT STARTER RELAY (ST)

CHECK HARNESS AND CONNECTOR (ST RELAY - PNP SWITCH, CLUTCH START SWITCH)

CHECK HARNESS AND CONNECTOR (POWER SOURCE)

INSPECT STARTER

INSPECT STARTER CUT RELAY (ST CUT)

CHECK HARNESS AND CONNECTOR (ST CUT RELAY - PNP SWITCH, ECM)

INSPECT PARK/NEUTRAL POSITION SWITCH

CHECK HARNESS AND CONNECTOR (PNP SWITCH - ECM)

CHECK HARNESS AND CONNECTOR (MAIN BODY ECU - ECM)

CHECK HARNESS AND CONNECTOR (ST CUT RELAY - PNP SWITCH, ECM)

INSPECT STARTER CUT RELAY (ST CUT)

CHECK HARNESS AND CONNECTOR (ST CUT RELAY - CLUTCH START SWITCH, ECM)

INSPECT CLUTCH START SWITCH ASSEMBLY

CHECK HARNESS AND CONNECTOR (CLUTCH START SWITCH - ECM)

CHECK HARNESS AND CONNECTOR (MAIN BODY ECU - ECM)

CHECK HARNESS AND CONNECTOR (ST CUT RELAY - CLUTCH START SWITCH SWITCH, ECM)

REPLACE ECM

CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED

SFI system - Cranking Holding Function Circuit

Description

The cranking holding control system provides current to the starter when the ECM detects the ignition switch start signal (STSW). When the ECM performs a firing judgment, the system cuts current to the starter. When an ECM receives the STSW signal, it turns on the ST CUT relay, which prevents flickering of the combination meter, clock, audio system, etc. Also, the ECM sends a signal to the STAR terminal of the ECM. Then the STAR output signal travels through the Park/Neutral Position (PNP) switch to the ST relay, causing the starter to activate.

When the engine is cranking, the starter operation signal is sent to the STA terminal of the ECM.

SFI system - Cranking Holding Function Circuit Land Cruiser 1GR-FE

Wiring diagram

Refer to DTC P0617.

Inspection procedure

1.CHECK CRANKING

  1. Check the cranking of the engine.

    Result
    Test Result Proceed to
    Cranking possible and holding control operates A
    Does not crank B
    Cranking possible but holding control does not operate (for automatic transmission) C
    Cranking possible but holding control does not operate (for manual transmission) D
  B  
Go to step 2
 
  C  
Go to step 11
 
  D  
Go to step 17
 
A  
   
PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE

2.READ VALUE USING INTELLIGENT TESTER (STARTER SIGNAL)

  1. Connect the intelligent tester to the DLC3.

  1. Turn the ignition switch to ON.

  1. Turn the intelligent tester on.

  1. Enter the following menus: Powertrain / Engine and ECT / Data List / Starter Signal.

  1. Read values.

  1. Check the result when the ignition switch is turned to ON and when the engine is started.

    OK:

    Condition Display (Starter Signal)
    Ignition switch ON OFF
    Engine is started ON
    Result
    Result Proceed to
    OK A
    NG (for automatic transmission) B
    NG (for manual transmission) C
  B  
Go to step 7
 
  C  
Go to step 13
 
A  
   

3.INSPECT STARTER RELAY (ST)

  1. Inspect the starter relay (ST).

  NG  
REPLACE STARTER RELAY (ST)
 
OK  
   

4.CHECK HARNESS AND CONNECTOR (ST RELAY - PNP SWITCH, CLUTCH START SWITCH)

Disconnect the Park/Neutral Position (PNP) switch (for automatic transmission). SFI system - Cranking Holding Function Circuit Land Cruiser 1GR-FE

  1. Disconnect the Park/Neutral Position (PNP) switch (for automatic transmission).

  1. Disconnect the clutch start switch (for manual transmission).

  1. Remove the ST relay from the engine room relay block.

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

    Standard Resistance (Check for Open):

    for automatic transmission:

    Tester Connection Condition Specified Condition
    ST relay (1) - C24-5 Always Below 1 ?

    Standard Resistance (Check for Short):

    for automatic transmission:

    Tester Connection Condition Specified Condition
    ST relay (1) or C24-5 - Body ground Always 10 k? or higher

    Standard Resistance (Check for Open):

    for manual transmission:

    Tester Connection Condition Specified Condition
    ST relay (1) - A49-2*1 Always Below 1 ?
    ST relay (1) - e1-2*2 Always Below 1 ?

    Standard Resistance (Check for Short):

    for manual transmission:

    Tester Connection Condition Specified Condition
    ST relay (1) or A49-2*1 - Body ground Always 10 k? or higher
    ST relay (1) or e1-2*2 - Body ground Always 10 k? or higher

    *1: for LHD

    *2: for RHD

  NG  
REPAIR OR REPLACE HARNESS OR CONNECTOR
 
OK  
   

5.CHECK HARNESS AND CONNECTOR (POWER SOURCE)

Remove the ST relay from the engine room relay block. SFI system - Cranking Holding Function Circuit Land Cruiser 1GR-FE

  1. Remove the ST relay from the engine room relay block.

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

    Standard Voltage:

    Tester Connection Condition Specified Condition
    ST relay (2) - ST relay (5) Always 11 to 14 V
  NG  
REPAIR OR REPLACE HARNESS OR CONNECTOR (STARTER RELAY (ST) - BATTERY, BODY GROUND)
 
OK  
   

6.INSPECT STARTER

  1. Inspect the starter (for 1.4 kW Type) .

  1. Inspect the starter (for 2.0 kW Type) .

Result
Result Proceed to
OK A
NG (for 1.4 kW Type) B
NG (for 2.0 kW Type) C
  B  
REPLACE STARTER
 
  C  
REPLACE STARTER
 
A  
   
REPAIR OR REPLACE HARNESS OR CONNECTOR (STARTER - STARTER RELAY (ST), BATTERY)

7.INSPECT STARTER CUT RELAY (ST CUT)

  1. Inspect the starter cut relay (ST CUT).

  NG  
REPLACE STARTER CUT RELAY (ST CUT)
 
OK  
   

8.CHECK HARNESS AND CONNECTOR (ST CUT RELAY - PNP SWITCH, ECM)

Remove the starter cut relay (ST CUT) from the engine room relay block. SFI system - Cranking Holding Function Circuit Land Cruiser 1GR-FE

  1. Remove the starter cut relay (ST CUT) from the engine room relay block.

  1. Disconnect the PNP switch connector.

  1. Disconnect the ECM connector.

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

    Standard Resistance (Check for Open):

    Tester Connection Condition Specified Condition
    ST CUT relay (5) - C45-63 (STAR) Always Below 1 ?
    ST CUT relay (3) - C24-4 Always Below 1 ?

    Standard Resistance (Check for Short):

    Tester Connection Condition Specified Condition
    ST CUT relay (5) or C45-63 (STAR) - Body ground Always 10 k? or higher
    ST CUT relay (3) or C24-4 - Body ground Always 10 k? or higher
  NG  
REPAIR OR REPLACE HARNESS OR CONNECTOR
 
OK  
   

9.INSPECT PARK/NEUTRAL POSITION SWITCH

Inspect the Park/Neutral Position (PNP) switch. SFI system - Cranking Holding Function Circuit Land Cruiser 1GR-FE

  1. Inspect the Park/Neutral Position (PNP) switch.

    1. Disconnect the PNP switch connector.

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

      Standard Resistance:

      Tester Connection Condition Specified Condition
      4 (B) - 5 (L) Shift lever in P Below 1 ?
      Shift lever in N Below 1 ?
  NG  
REPLACE PARK/NEUTRAL POSITION SWITCH ASSEMBLY
 
OK  
   

10.CHECK HARNESS AND CONNECTOR (PNP SWITCH - ECM)

Disconnect the PNP switch connector. SFI system - Cranking Holding Function Circuit Land Cruiser 1GR-FE

  1. Disconnect the PNP switch connector.

  1. Disconnect the ECM connector.

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

    Standard Resistance (Check for Open):

    Tester Connection Condition Specified Condition
    C24-5 - A38-48 (STA) Always Below 1 ?

    Standard Resistance (Check for Short):

    Tester Connection Condition Specified Condition
    C24-5 or A38-48 (STA) - Body ground Always 10 k? or higher
    Result
    Result Proceed to
    NG A
    OK B
  B  
Go to step 19
 
A  
   
REPAIR OR REPLACE HARNESS OR CONNECTOR

11.CHECK HARNESS AND CONNECTOR (MAIN BODY ECU - ECM)
Disconnect the main body ECU connector. SFI system - Cranking Holding Function Circuit Land Cruiser 1GR-FE

  1. Disconnect the main body ECU connector.

  1. Disconnect the ECM connector.

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

    Standard Resistance (Check for Open):

    Tester Connection Condition Specified Condition
    E4-4 (STSW) - A38-14 (STSW) Always Below 1 ?

    Standard Resistance (Check for Short):

    Tester Connection Condition Specified Condition
    E4-4 (STSW) or A38-14 (STSW) - Body ground Always 10 k? or higher
  NG  
REPAIR OR REPLACE HARNESS OR CONNECTOR
 
OK  
   

12.CHECK HARNESS AND CONNECTOR (ST CUT RELAY - PNP SWITCH, ECM)

Remove the starter cut relay (ST CUT) from the engine room relay block. SFI system - Cranking Holding Function Circuit Land Cruiser 1GR-FE

  1. Remove the starter cut relay (ST CUT) from the engine room relay block.

  1. Disconnect the PNP switch connector.

  1. Disconnect the ECM connector.

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

    Standard Resistance (Check for Open):

    Tester Connection Condition Specified Condition
    ST CUT relay (5) - C45-63 (STAR) Always Below 1 ?
    ST CUT relay (3) - C24-4 Always Below 1 ?

    Standard Resistance (Check for Short):

    Tester Connection Condition Specified Condition
    ST CUT relay (5) or C45-63 (STAR) - Body ground Always 10 k? or higher
    ST CUT relay (3) or C24-4 - Body ground Always 10 k? or higher
  NG  
REPAIR OR REPLACE HARNESS OR CONNECTOR
 
OK  
   
REPLACE ECM

13.INSPECT STARTER CUT RELAY (ST CUT)

  1. Inspect the starter cut relay (ST CUT).

  NG  
REPLACE STARTER CUT RELAY (ST CUT)
 
OK  
   

14.CHECK HARNESS AND CONNECTOR (ST CUT RELAY - CLUTCH START SWITCH, ECM)

Remove the starter cut relay (ST CUT) from the engine room relay block. SFI system - Cranking Holding Function Circuit Land Cruiser 1GR-FE

  1. Remove the starter cut relay (ST CUT) from the engine room relay block.

  1. Disconnect the clutch start switch connector.

  1. Disconnect the ECM connector.

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

    Standard Resistance (Check for Open):

    for LHD
    Tester Connection Condition Specified Condition
    ST CUT relay (5) - C45-63 (STAR) Always Below 1 ?
    ST CUT relay (3) - A49-1 Always Below 1 ?
    for RHD
    Tester Connection Condition Specified Condition
    ST CUT relay (5) - C46-63 (STAR) Always Below 1 ?
    ST CUT relay (3) - e1-1 Always Below 1 ?

    Standard Resistance (Check for Short):

    for LHD
    Tester Connection Condition Specified Condition
    ST CUT relay (5) or C45-63 (STAR) - Body ground Always 10 k? or higher
    ST CUT relay (3) or A49-1 - Body ground Always 10 k? or higher
    for RHD
    Tester Connection Condition Specified Condition
    ST CUT relay (5) or C46-63 (STAR) - Body ground Always 10 k? or higher
    ST CUT relay (3) or e1-1 - Body ground Always 10 k? or higher
  NG  
REPAIR OR REPLACE HARNESS OR CONNECTOR
 
OK  
   

15.INSPECT CLUTCH START SWITCH ASSEMBLY

  1. Inspect the clutch start switch (for LHD) .

  1. Inspect the clutch start switch (for RHD) .

    Result
    Result Proceed to
    OK A
    NG (for LHD) B
    NG (for RHD) C
  B  
REPLACE CLUTCH START SWITCH ASSEMBLY
 
  C  
REPLACE CLUTCH START SWITCH ASSEMBLY
 
A  
   

16.CHECK HARNESS AND CONNECTOR (CLUTCH START SWITCH - ECM)

Disconnect the clutch start switch connector. SFI system - Cranking Holding Function Circuit Land Cruiser 1GR-FE

  1. Disconnect the clutch start switch connector.

  1. Disconnect the ECM connector.

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

    Standard Resistance (Check for Open):

    for LHD
    Tester Connection Condition Specified Condition
    A49-2 - A38-48 (STA) Always Below 1 ?
    for RHD
    Tester Connection Condition Specified Condition
    e1-2 - A52-48 (STA) Always Below 1 ?

    Standard Resistance (Check for Short):

    for LHD
    Tester Connection Condition Specified Condition
    A49-2 or A38-48 (STA) - Body ground Always 10 k? or higher
    for RHD
    Tester Connection Condition Specified Condition
    e1-2 or A52-48 (STA) - Body ground Always 10 k? or higher
    Result
    Result Proceed to
    NG A
    OK B
  B  
Go to step 19
 
A  
   
REPAIR OR REPLACE HARNESS OR CONNECTOR

17.CHECK HARNESS AND CONNECTOR (MAIN BODY ECU - ECM)
Disconnect the main body ECU connector. SFI system - Cranking Holding Function Circuit Land Cruiser 1GR-FE

  1. Disconnect the main body ECU connector.

  1. Disconnect the ECM connector.

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

    Standard Resistance (Check for Open):

    for LHD
    Tester Connection Condition Specified Condition
    E4-4 (STSW) - A38-14 (STSW) Always Below 1 ?
    for RHD
    Tester Connection Condition Specified Condition
    E4-4 (STSW) - A52-14 (STSW) Always Below 1 ?

    Standard Resistance (Check for Short):

    for LHD
    Tester Connection Condition Specified Condition
    E4-4 (STSW) or A38-14 (STSW) - Body ground Always 10 k? or higher
    for RHD
    Tester Connection Condition Specified Condition
    E4-4 (STSW) or A52-14 (STSW) - Body ground Always 10 k? or higher
  NG  
REPAIR OR REPLACE HARNESS OR CONNECTOR
 
OK  
   

18.CHECK HARNESS AND CONNECTOR (ST CUT RELAY - CLUTCH START SWITCH SWITCH, ECM)

Remove the starter cut relay (ST CUT) from the engine room relay block SFI system - Cranking Holding Function Circuit Land Cruiser 1GR-FE

  1. Remove the starter cut relay (ST CUT) from the engine room relay block.

  1. Disconnect the clutch start switch connector.

  1. Disconnect the ECM connector.

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

    Standard Resistance (Check for Open):

    for LHD
    Tester Connection Condition Specified Condition
    ST CUT relay (5) - C45-63 (STAR) Always Below 1 ?
    ST CUT relay (3) - A49-1 Always Below 1 ?
    for RHD
    Tester Connection Condition Specified Condition
    ST CUT relay (5) - C46-63 (STAR) Always Below 1 ?
    ST CUT relay (3) - e1-1 Always Below 1 ?

    Standard Resistance (Check for Short):

    for LHD
    Tester Connection Condition Specified Condition
    ST CUT relay (5) or C45-63 (STAR) - Body ground Always 10 k? or higher
    ST CUT relay (3) or A49-1 - Body ground Always 10 k? or higher
    for RHD
    Tester Connection Condition Specified Condition
    ST CUT relay (5) or C46-63 (STAR) - Body ground Always 10 k? or higher
    ST CUT relay (3) or e1-1 - Body ground Always 10 k? or higher
  NG  
REPAIR OR REPLACE HARNESS OR CONNECTOR
 
OK  
   
REPLACE ECM

19.REPLACE ECM

  1. Replace the ECM .

NEXT  
   

20.CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED

  1. Check the starter operation.

    OK:

    Malfunction has been repaired successfully.

  NG  
GO TO ENTRY AND START SYSTEM (ENGINE DOES NOT START)
 
OK  
   
END