STOP AND START SYSTEM, Diagnostic DTC:P161D

DTC Code DTC Name
P161D Starter Delay Circuit

DESCRIPTION

By using the starter delay circuit, the engine stop and start ECU can activate the ST NO. 2 relay (for starter motor operation) after activating the ST relay (for starter pinion operation) to operate the starter assembly.

By monitoring the condition of the ST relay (for starter pinion operation) and ST NO. 2 relay (for starter motor operation), the engine stop and start ECU detects if the transistor of the starter delay circuit is stuck. If the transistor of the starter delay circuit is stuck on, the engine stop and start ECU blinks the stop and start cancel indicator and stores DTC P161D. If the transistor of the starter delay circuit is stuck on, the ST relay (for starter pinion operation) and ST NO. 2 relay (for starter motor operation) will be activated simultaneously.

A01W5BUE05
DTC No. DTC Detection Condition Trouble Area
P161D

Both of the following conditions are met (1 trip detection logic):


  • Engine switch on (IG)

  • Time between ST relay (for starter pinion) turning on and ST NO. 2 relay (for starter motor) turning on becomes less than 0.016 seconds and 3 times or more

 Engine stop and start ECU

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


    • If the cable is disconnected from the negative (-) battery terminal, stop and start control is prohibited until refresh charge is completed. In this case, drive the vehicle approximately 5 to 60 minutes until refresh charge is completed and stop and start control operation is permitted.

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


    1. Connect the GTS to the DLC3.

    2. Turn the engine switch on (IG) and turn the GTS on.

    3. Clear the DTCs.

    4. Start the engine and warm it up.

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

      CAUTION:

      When performing Confirmation Driving Pattern, obey all speed limits and traffic laws.

    6. Depress the brake pedal and stop the vehicle.

    7. Keep the engine stopped by stop and start control. (Keep the shift lever in D.)

    8. Release the brake pedal with the shift lever in D to start the engine.

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

      CAUTION:

      When performing Confirmation Driving Pattern, obey all speed limits and traffic laws.

    10. Depress the brake pedal and stop the vehicle.

    11. Keep the engine stopped by stop and start control. (Keep the shift lever in D.)

    12. Release the brake pedal with the shift lever in D to start the engine.

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

      CAUTION:

      When performing Confirmation Driving Pattern, obey all speed limits and traffic laws.

    14. Depress the brake pedal and stop the vehicle.

    15. Keep the engine stopped by stop and start control. (Keep the shift lever in D.)

    16. Release the brake pedal with the shift lever in D to start the engine.

    17. Check that no DTCs are output.

  2. STOP AND START SYSTEM OPERATION CHECK

    Tech Tips

    If the cable is disconnected from the negative (-) battery terminal, stop and start control is prohibited until refresh charge is completed. In this case, drive the vehicle approximately 5 to 60 minutes until refresh charge is completed and stop and start control operation is permitted.


    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.

      Note

      When performing Confirmation Driving Pattern, obey all speed limits and traffic laws.

    4. Depress the brake pedal and stop the vehicle.

    5. Allow the engine to stop by stop and start control. (Keep the shift lever in D.)

    6. Release the brake pedal with the shift lever in D to start the engine.

WIRING DIAGRAM

Refer to DTC P0617 Click here.

CAUTION / NOTICE / HINT

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 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 airbag sensor assembly, clear and calibrate the deceleration sensor zero point in the engine stop and start ECU Click here.

Tech Tips

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. CHECK ENGINE STOP AND START ECU (STA, STA2 SIGNAL)


    1. Connect an oscilloscope to the A77-21 (STA), A77-23 (STA2) and A77-6 (DGND) terminals of the engine stop and start ECU connector.

      A01W4DYE02
      Text in Illustration
      *a

      Component with harness connected

      (Engine Stop and Start ECU)

      		 - -
    2. A01W3KFE29
      *1 (ST Relay)
      *2 (ST NO. 2 Relay)
      *3 0.016 seconds or more

      Check the waveform immediately after turning the engine switch on (START).

      Item Condition
      Tester Connection

      A77-21 (STA) - A77-6 (DGND)

      A77-23 (STA2) - A77-6 (DGND)
      Condition Engine started by engine switch operation
      Result
      Result Proceed to
      Time between ST relay (for starter pinion) turning on and ST NO. 2 relay (for starter motor) turning on becomes 0.016 seconds or more A
      Time between ST relay (for starter pinion) turning on and ST NO. 2 relay (for starter motor) turning on becomes less than 0.016 seconds B

    A

    USE SIMULATION METHOD TO CHECK Click here

    B

    REPLACE ENGINE STOP AND START ECU Click here