STOP AND START SYSTEM, Diagnostic DTC:P1545

DTC Code DTC Name
P1545 Starter Maintenance

DESCRIPTION

When the number of starter operations reaches the maximum number, the engine stop and start ECU stores DTC P1545 and blinks the stop and start cancel indicator light. When the STA signal detected by the ECM and the engine stop and start ECU do not match, the engine stop and start ECU stores DTC P1545 and blinks the stop and start cancel indicator light.

DTC No. DTC Detection Condition Trouble Area
P1545

The following conditions are met (1 trip detection logic):


  • The number of starter operations reaches the specified limit.

  • Ignition switch is turned to ON

Both of the following conditions continue for 2 seconds or more (1 trip detection logic):


  • Normal communication with the ECM.

  • STA signals detected by the ECM and the engine stop and start ECU do not match.

  • Wire harness or connector

  • ST relay

  • Engine stop and start ECU

  • Starter assembly

  • ECM

CONFIRMATION DRIVING PATTERN

Tech Tips

DTCs for the stop and start system are not cleared even if the malfunction has been repaired. After repairing the malfunction, be sure to clear the DTCs Click here.


  1. CONFIRMATION AFTER TROUBLESHOOTING

    Tech Tips


    • When the cable is disconnected from the negative (-) battery terminal, stop and start control is prohibited for a certain amount of time. After connecting the cable, drive the vehicle until stop and start control is permitted (approximately 15 to 40 minutes).

    • Allow the engine to idle for 3 minutes after the engine warms up and check that the engine speed is within 50 rpm of the target idle speed.


    1. Connect the GTS to the DLC3.

    2. Turn the ignition switch to ON and turn the GTS on.

    3. Clear the DTCs Click here.

    4. Start the engine and warm it up.

    5. Drive the vehicle at 7 km/h (4.3 mph) or more.

      CAUTION:

      When performing the confirmation driving pattern, obey all speed limits and traffic laws.

    6. Stop the vehicle, move the shift lever to neutral and release the clutch pedal.

    7. Keep the engine stopped by stop and start control for 1 second or more.

    8. Depress the clutch pedal and start the engine.

    9. Check that DTCs are not output Click here.

  2. STOP AND START SYSTEM OPERATION CHECK

    Tech Tips

    When the cable is disconnected from the negative (-) battery terminal, stop and start control is prohibited for a certain amount of time. After connecting the cable, drive the vehicle until stop and start control is permitted (approximately 15 to 40 minutes).


    1. Start the engine and warm it up.

    2. Turn the air conditioning system off.

    3. Drive the vehicle at 7 km/h (4.3 mph) or more.

      CAUTION:

      When performing the confirmation driving pattern, obey all speed limits and traffic laws.

    4. Stop the vehicle, move the shift lever to neutral and release the clutch pedal.

    5. Allow the engine to stop by stop and start control.

    6. Depress the clutch pedal and start the engine.

WIRING DIAGRAM

Refer to DTC P0617 Click here.

INSPECTION PROCEDURE

Note


  • Before replacing the engine stop and start ECU, read the number of starter operations and write it into a new engine stop and start ECU Click here.

  • After replacing the starter assembly, perform initialization of the number of starter operations stored in the engine stop and start ECU Click here.

  • After replacing the engine stop and start ECU or air conditioning amplifier assembly, reset and perform learning of the air conditioning information in the engine stop and start ECU Click here.

  • After replacing the engine stop and start ECU or yaw rate sensor, perform deceleration sensor zero point clear and calibration Click here.

  • Inspect the fuses for circuits related to this system before performing the following procedure.

Tech Tips


  • DTCs for the stop and start system are not cleared even if the malfunction has been repaired. After repairing the malfunction, be sure to clear the DTCs Click here.

  • Using the GTS, read the freeze frame data before troubleshooting. System condition information is recorded as freeze frame data the moment a DTC is stored. This information can be useful when troubleshooting Click here.

PROCEDURE


  1. READ VALUE USING GTS (STARTER OPERATION #)


    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 / Stop and Start / Data List / Starter Operation #.

    5. Read the Starter Operation # value displayed on the GTS.

      Result
      Result Proceed to
      Below 368000 A
      368000 or more B

    B

    REPLACE STARTER ASSEMBLY Click here

    A

  2. READ VALUE USING GTS (STARTER SIGNAL)


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

    2. Depress the clutch pedal fully.

    3. Read the values displayed on the GTS when the ignition switch is turned to ON and START.

      OK
      GTS Display Switch Condition Normal Condition
      Starter Signal Ignition switch ON OFF
      Ignition switch START ON

    NG

    GO TO ECD SYSTEM (STARTER SIGNAL CIRCUIT) Click here

    OK

  3. CHECK ENGINE STOP AND START ECU (STA TERMINAL VOLTAGE)


    1. Turn the ignition switch to ON.

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

      Tech Tips

      If battery voltage drops below 8 V when cranking, CAN communication may be interrupted.

      A01IOHTE18
      Text in Illustration
      *a

      Component with harness connected

      (Engine Stop and Start ECU)

      		 - -
      Standard Voltage
      Tester Connection Condition Specified Condition
      A74-21 (STA) - Body ground Ignition switch ON 0 to 1.5 V
      Cranking 6 to 14 V

    NG

    INSPECT RELAY (ST RELAY) Click here

    OK

    USE SIMULATION METHOD TO CHECK Click here

  4. INSPECT RELAY (ST RELAY)


    1. Inspect the ST relay Click here.


    NG

    REPLACE RELAY (ST RELAY)

    OK

  5. CHECK HARNESS AND CONNECTOR (ENGINE STOP AND START ECU - ST RELAY)


    1. w/ Entry and Start System:

      Disconnect the power management control ECU connector.

    2. Disconnect the A74 engine stop and start ECU connector.

    3. Disconnect the ECM connector.

    4. Disconnect the clutch start switch assembly (for lower) connector.

    5. Remove the ST relay from the No. 3 relay block.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      A74-21 (STA) - ST relay terminal 2 Always Below 1 Ω
      A74-21 (STA) - Body ground Always 10 kΩ or higher
      ST relay terminal 2- Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  6. CHECK HARNESS AND CONNECTOR (ENGINE STOP AND START ECU - CLUTCH START SWITCH ASSEMBLY (FOR LOWER))


    1. w/ Entry and Start System:

      Disconnect the power management control ECU connector.

    2. Disconnect the A74 engine stop and start ECU connector.

    3. Disconnect the ECM connector.

    4. Disconnect the A4 clutch start switch assembly (for lower) connector.

    5. Remove the ST relay from the No. 3 relay block.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      A74-21 (STA) - A4-1 Always Below 1 Ω
      A4-1 - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  7. CHECK HARNESS AND CONNECTOR (ENGINE STOP AND START ECU - ECM)


    1. w/ Entry and Start System:

      Disconnect the power management control ECU connector.

    2. Disconnect the A74 engine stop and start ECU connector.

    3. Disconnect the A76 ECM connector.

    4. Disconnect the clutch start switch assembly (for lower) connector.

    5. Remove the ST relay from the No. 3 relay block.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      A74-21 (STA) - A76-36 (STA) Always Below 1 Ω
      A76-36 (STA) - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

    REPLACE ENGINE STOP AND START ECU Click here

  8. REPLACE STARTER ASSEMBLY


    1. Replace the starter assembly Click here.

      Tech Tips


      • When replacing a starter assembly that has exceeded the specified number of operations, other related parts may also be worn. Replace the ST relay and related fuses at the same time.

      • Clear the number of starter operations by performing "Starter Exchange" using the GTS Click here.


    NEXT

    END