STOP AND START SYSTEM, Diagnostic DTC:P1780

DTC Code DTC Name
P1780 Discrepancy between Neutral Position SW and Shift Position

DESCRIPTION

The engine stop and start ECU detects a malfunction by comparing the shift position signal with the neutral position switch signal input state. If a malfunction is detected, the engine stop and start ECU blinks the stop and start cancel indicator light, prohibits the stop and start control and stores DTC P1780. (for Manual Transaxle)

The engine stop and start ECU detects malfunctions by comparing the conditions of the shift position signal and NSW signal. If a malfunction is detected, the engine stop and start ECU blinks the stop and start cancel indicator light, prohibits stop and start control and stores DTC P1780. (for CVT)

DTC No. Detection Item DTC Detection Condition Trouble Area Warning Indicate Memory
P1780 Discrepancy between Neutral Position SW and Shift Position

The following condition continues for 1 seconds or more (1 trip detection logic) (for Manual Transaxle):


  • Open or short in neutral position switch circuit.

Both of the following conditions are met for 2 seconds or more (2 trip detection logic) (for CVT) (*1):


  • Ignition switch ON

  • NSW signal is ON with the shift lever in D

Both of the following conditions are met for 2 seconds or more (2 trip detection logic) (for CVT) (*1):


  • Ignition switch ON

  • NSW signal is ON with the shift lever in R

Both of the following conditions are met for 15 seconds or more (2 trip detection logic) (for CVT) (*2):


  • Ignition switch ON

  • NSW signal is ON with the shift lever in P or N

  • Neutral position switch (for Manual Transaxle)

  • Park/neutral position switch assembly (for CVT)

  • Engine stop and start ECU

  • Wire harness or connector

 Blinking DTC stored

*1: "ON" is displayed for the freeze frame data item [Neutral Switch Stuck ON]

*2: "ON" is displayed for the freeze frame data item [Neutral Switch Stuck OFF]

WIRING DIAGRAM


  1. for Manual Transaxle

    B0042P7E22
    *a Neutral Position Switch
    *b Engine Stop and Start ECU

  2. for CVT

    B0042NSE04

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. CONFIRM MODEL


    1. Choose the model to be inspected.

      Result
      Result Proceed to
      for Manual Transaxle A
      for CVT B

    B

    READ VALUE USING GTS Click here

    A

  2. READ VALUE USING GTS (NEUTRAL SWITCH)


    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 / Neutral Switch.


      Powertrain > Stop and Start > Data List
      Tester Display
      Neutral Switch

    5. Read the value when the shift lever is in neutral and any other position

      OK
      Tester Display Condition Normal Condition
      Neutral Switch Shift lever in neutral ON
      Shift lever in any position other than neutral OFF
      Result
      Proceed to
      OK
      NG

    OK

    USE SIMULATION METHOD TO CHECK Click here

    NG

  3. CHECK HARNESS AND CONNECTOR (ENGINE STOP AND START ECU - NEUTRAL POSITION SWITCH)


    1. Disconnect the A9 engine stop and start ECU connector.

    2. Disconnect the B100 neutral position switch connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      A9-26 (TMVC) - B100-1 (W1) Always Below 1 Ω
      A9-25 (TME2) - B100-3 (F+) Always Below 1 Ω
      A9-27 (TMN) - B100-2 (TMN) Always Below 1 Ω
      A9-26 (TMVC) - Body ground Always 10 kΩ or higher
      B100-1 (W1) - Body ground Always 10 kΩ or higher
      A9-25 (TME2) - Body ground Always 10 kΩ or higher
      B100-3 (F+) - Body ground Always 10 kΩ or higher
      A9-27 (TMN) - Body ground Always 10 kΩ or higher
      B100-2 (TMN) - Body ground Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  4. CHECK ENGINE STOP AND START ECU (TMN TERMINAL VOLTAGE)


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

      B0042LKC23
      *a

      Component with harness connected

      (Engine Stop and Start ECU)

      		 - -
      Standard Voltage
      Tester Connection Condition Specified Condition
      A9-27 (TMN) - A9-25 (TME2) Ignition switch ON, shift lever in neutral 2.7 to 4.3 V
      Ignition switch ON, shift lever in any position other than neutral 0.7 to 1.9 V
      Result
      Proceed to
      OK
      NG

    OK

    REPLACE ENGINE STOP AND START ECU Click here

    NG

    REPLACE NEUTRAL POSITION SWITCH for 1WW: Click here
    REPLACE NEUTRAL POSITION SWITCH for 1ND-TV: Click here
    REPLACE NEUTRAL POSITION SWITCH for 8NR-FTS: Click here

  5. READ VALUE USING GTS


    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.

    5. In accordance with the display on the GTS, read the Data List.


      Powertrain > ECT > Data List
      Tester Display Measurement Item Range Normal Condition Diagnostic Note
      Shift SW Status (P Range) Park/neutral position switch assembly status OFF or ON

      OFF: Shift lever not in P

      ON: Shift lever in P

      		 -
      Shift SW Status (R Range) Park/neutral position switch assembly status OFF or ON

      OFF: Shift lever not in R

      ON: Shift lever in R

      		 -
      Shift SW Status (N Range) Park/neutral position switch assembly status OFF or ON

      OFF: Shift lever not in N

      ON: Shift lever in N

      		 -
      Shift SW Status (D Range) Park/neutral position switch assembly status OFF or ON

      OFF: Shift lever not in D or M

      ON: Shift lever in D or M

      		 -

      Powertrain > ECT > Data List
      Tester Display
      Shift SW Status (P Range)
      Shift SW Status (R Range)
      Shift SW Status (N Range)
      Shift SW Status (D Range)
      Result
      Proceed to
      OK
      NG

    NG

    INSPECT PARK/NEUTRAL POSITION SWITCH ASSEMBLY Click here

    OK

  6. READ VALUE USING GTS (NEUTRAL POSITION SW OR NEUTRAL POSITION SW SIGNAL)


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

    2. In accordance with the display on the GTS, read the Data List.


      Powertrain > ECT > Data List
      Tester Display Measurement Item Range Normal Condition Diagnostic Note
      Neutral Position SW Signal Park/neutral position switch assembly status OFF or ON

      OFF: Shift lever not in P or N

      ON: Shift lever in P or N

      		 -

      Powertrain > ECT > Data List
      Tester Display
      Neutral Position SW Signal
      Result
      Proceed to
      OK
      NG

    OK

    USE SIMULATION METHOD TO CHECK Click here

    NG

  7. INSPECT PARK/NEUTRAL POSITION SWITCH ASSEMBLY


    1. Inspect the park/neutral position switch assembly.

      Click here

      Result
      Proceed to
      OK
      NG

    NG

    REPLACE PARK/NEUTRAL POSITION SWITCH ASSEMBLY Click here

    OK

  8. CHECK HARNESS AND CONNECTOR (ENGINE STOP AND START ECU - PARK/NEUTRAL POSITION SWITCH ASSEMBLY)


    1. Disconnect the A9 engine stop and start ECU connector.

    2. Disconnect the B110 park/neutral position switch assembly connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      A9-21 (STA) - B110-9 (L) Always Below 1 Ω
      A9-28 (CLL) - B110-4 (B) Always Below 1 Ω
      A9-21 (STA) - Body ground Always 80 to 180 Ω
      A9-28 (CLL) - Body ground Always 10 kΩ or higher
      B110-9 (L) - Body ground Always 80 to 180 Ω
      B110-4 (B) - Body ground Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    OK

    REPLACE ENGINE STOP AND START ECU Click here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

  9. INSPECT PARK/NEUTRAL POSITION SWITCH ASSEMBLY


    1. Inspect the park/neutral position switch assembly.

      Click here

      Result
      Proceed to
      OK
      NG

    NG

    REPLACE PARK/NEUTRAL POSITION SWITCH ASSEMBLY Click here

    OK

  10. CHECK HARNESS AND CONNECTOR (ECM - PARK/NEUTRAL POSITION SWITCH ASSEMBLY)


    1. Disconnect the A173 and B208 ECM connectors.

    2. Disconnect the B110 park/neutral position switch assembly connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      B208-64 (P) - B110-3 (PL) Always Below 1 Ω
      B208-35 (R) - B110-2 (RL) Always Below 1 Ω
      B208-65 (N) - B110-8 (NL) Always Below 1 Ω
      B208-34 (D) - B110-7 (DL) Always Below 1 Ω
      A173-57 (NSW) - B110-4 (B) Always Below 1 Ω
      Result
      Proceed to
      OK
      NG

    OK

    REPLACE ECM Click here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR