SFI SYSTEM Cranking Holding Function Circuit

DESCRIPTION

w/ Entry and Start System

• When cranking the engine, the starter motor drive signal (STA2 signal) transmitted by the engine stop and start ECU is received by the ECM as the starter operation signal (STA signal), and then the ECM controls the engine. When an engine start signal is output from the engine switch, the certification ECU (smart key ECU assembly) transmits the starter operation signal (STA signal) to the ST relay (starter pinion drive relay) and the starter operation signal (STA signal) to the engine stop and start ECU through the park/neutral position switch assembly. Afterwards, the engine stop and start ECU transmits the starter motor drive signal (STA2 signal) to the ST2 relay through the delay circuit, and drives the starter until a stable engine speed signal (NE signal) is detected.

WIRING DIAGRAM

CAUTION / NOTICE / HINT

PROCEDURE

1. WHETHER ENGINE CAN BE CRANKED

   
   

   1. Check if the engine can be cranked.

      RESULT
      Result Proceed to Engine cannot be cranked A Engine can be cranked B

   
   

   B

   READ VALUE USING GTS (STARTER SIGNAL) Click here

   A

2. READ VALUE USING GTS (STARTER SIGNAL)

   
   

   1. Connect the GTS to the DLC3.

   2. Turn the ignition switch to ON.

   3. Turn the GTS on.

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

   5. Read the value displayed on the GTS when the ignition switch is turned to ON and START.

      OK
      Ignition Switch Position Starter Signal ON Close(OFF) START OPEN(ON)

   
   

   OK

   GO TO ENTRY AND START SYSTEM Click here

   NG

3. CHECK HARNESS AND CONNECTOR (ECM - ENGINE STOP AND START ECU -ST2 RELAY)

   
   

   1. Disconnect the ECM connector.

   2. Disconnect the engine stop and start ECU connector.

   3. Remove the ST2 relay from the engine room relay block.

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

      Standard Resistance
      Tester Connection Condition Specified Condition A58-22 (STA) - A73-23 (STA2) Always Below 1 Ω A58-22 (STA) - ST2 relay terminal 2) Always Below 1 Ω A58-22 (STA) - Body ground Always 10 kΩ or higher A73-23 (STA2) - Body ground Always 10 kΩ or higher ST2 relay terminal 2 - Body ground Always 10 kΩ or higher

   
   

   NG

   REPAIR OR REPLACE HARNESS AND CONNECTOR (ECM - ENGINE STOP AND START ECU - ST2 RELAY)

   OK

4. CHECK HARNESS AND CONNECTOR (ECM - CERTIFICATION ECU - STOP AND START ECU - PARK / NEUTRAL POSITION SWITCH ASSEMBLY)

   
   

   1. Disconnect the ECM connector.

   2. Disconnect the engine stop and start ECU connector.

   3. Disconnect the park/neutral position switch assembly connector.

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

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

      Standard Resistance
      Tester Connection Condition Specified Condition B23-63 (NSW) - A73-28 (CLL) Always Below 1 Ω B23-63 (NSW) - B69-4 (B) Always Below 1 Ω B23-63 (NSW) - F65-5 (STAR) Always Below 1 Ω B23-63 (NSW) - Body ground Always 10 kΩ or higher A73-28 (CLL) - Body ground Always 10 kΩ or higher B69-4 (B) - Body ground Always 10 kΩ or higher F65-5 (STAR) - Body ground Always 10 kΩ or higher

   
   

   OK

   PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE Click here

   NG

   REPAIR OR REPLACE HARNESS AND CONNECTOR (ECM - CERTIFICATION ECU - STOP AND START ECU - PARK / NEUTRAL POSITION SWITCH ASSEMBLY)

5. READ VALUE USING GTS (STARTER SIGNAL)

   
   

   1. Connect the GTS to the DLC3.

   2. Turn the ignition switch to ON.

   3. Turn the GTS on.

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

   5. Read the value displayed on the GTS when the ignition switch is turned to ON and START.

      OK
      Ignition Switch Position Starter Signal ON Close(OFF) START OPEN(ON)

   
   

   OK

   PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE Click here

   NG

   REPAIR OR REPLACE HARNESS AND CONNECTOR (ECM - ST2 RELAY)