STOP AND START SYSTEM, Diagnostic DTC:P1780

DTC Code DTC Name
P1780 Park / Neutral Position Switch Malfunction

DESCRIPTION

The engine stop and start ECU detects a malfunction by comparing the shift position signal with the park/neutral position switch signal*1 or neutral position switch signal*2 input state. When a malfunction occurs, the engine stop and start ECU stores P1780, blinks the stop and start cancel indicator light, and stops the stop and start system control.


for CVT
DTC No. Freeze Frame Data * DTC Detection Condition Trouble Area
P1780 Neutral switch malfunction (stuck ON)

Either of the following condition continues for 2 seconds or more (2 trip detection logic):


  • The park/neutral position switch signal is on and no starter input exists with the shift lever in D.

  • The park/neutral position switch signal is on and no starter input exists with the shift lever in R.

  • Park/neutral position switch

  • Engine stop and start ECU

  • ECM

  • Wire harness or connector
Neutral switch malfunction (stuck OFF) The park/neutral position switch signal is off and no starter output exists with the shift lever in P or N for 15 seconds or more (2 trip detection logic).

  • Park/neutral position switch

  • Engine stop and start ECU

  • ECM

  • Wire harness or connector

*: Since each information can be confirmed by freeze frame data, record the freeze frame data before deleting the diagnosis code.

for Manual Transaxle
DTC No. DTC Detection Condition Trouble Area
P1780 Open or short in neutral position switch circuit. for 1 second or more (1 trip detection logic).

  • Neutral position switch

  • Engine stop and start ECU

  • Wire harness or connector

WIRING DIAGRAM


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 control 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.

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

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 SPECIFICATIONS


    1. Check the vehicle specifications.

      Result
      Result Proceed to
      for CVT A
      for Manual Transaxle B

    B

    READ VALUE USING GTS (NEUTRAL SWITCH) Click here

    A

  2. READ VALUE USING GTS (SHIFT SW STATUS)


    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.

      Tester Display Measurement Item / Range Normal Condition Diagnostic Note
      Shift SW Status (P Range)

      Park/neutral position switch status /

      ON or OFF

      ON: Shift lever in P

      OFF: Shift lever not in P

      		 -
      Shift SW Status (R Range)

      Park/neutral position switch status /

      ON or OFF

      ON: Shift lever in R

      OFF: Shift lever not in R

      		 -
      Shift SW Status (N Range)

      Park/neutral position switch status /

      ON or OFF

      ON: Shift lever in N

      OFF: Shift lever not in N

      		 -
      Shift SW Status (D Range)

      Park/neutral position switch status /

      ON or OFF

      ON: Shift lever in D or M

      OFF: Shift lever not in D or M

      		 -
      Result
      Result Proceed to
      Data display is within Normal Condition range A
      Data display is not within Normal Condition range B

    B

    INSPECT PARK/NEUTRAL POSITION SWITCH Click here

    A

  3. READ VALUE USING GTS (NEUTRAL POSITION SW 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 / Neutral Position SW Signal.

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

      Tester Display Measurement Item / Range Normal Condition Diagnostic Note
      Neutral Position SW Signal

      Park/neutral position switch status /

      ON or OFF

      ON: Shift lever in P or N

      OFF: Shift lever not in P or N

      		 -
      Result
      Result Proceed to
      Data display is not within Normal Condition range A
      Data display is within Normal Condition range B

    B

    USE SIMULATION METHOD TO CHECK Click here

    A

  4. INSPECT PARK/NEUTRAL POSITION SWITCH


    1. Inspect the park/neutral position switch Click here.


    NG

    REPLACE PARK/NEUTRAL POSITION SWITCH Click here

    OK

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


    1. Disconnect the A92 engine stop and start ECU connector.

    2. Disconnect the B100 park/neutral position switch connector.

    3. Disconnect the A58 ECM connector.

    4. Disconnect the F13 ignition or starter switch assembly connector.

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

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      A92-21 (STA) - B100-9 (L) Always Below 1 Ω
      A92-28 (CLL) - B100-4 (B) Always Below 1 Ω
      A92-21 (STA), B100-9 (L) or ST relay holder 2 - Body ground Always 10 kΩ or higher
      A92-28 (CLL), B100-4 (B), F13-7(ST2) or A58-23(NSW) - Body ground Always 10 kΩ or higher

    OK

    REPLACE ENGINE STOP AND START ECU Click here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

  6. INSPECT PARK/NEUTRAL POSITION SWITCH


    1. Inspect the park/neutral position switch Click here.


    NG

    REPLACE PARK/NEUTRAL POSITION SWITCH Click here

    OK

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


    1. Disconnect the A92 engine stop and start ECU

    2. Disconnect the B100 park/neutral position switch connector.

    3. Disconnect the B22 ECM connector.

    4. Disconnect the F13 ignition or starter switch assembly connector.

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

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      B22-99 (P) - B100-3 (PL) Always Below 1 Ω
      B22-79 (R) - B100-2 (RL) Always Below 1 Ω
      B22-97 (N) - B100-8 (NL) Always Below 1 Ω
      B22-81 (D) - B100-7 (DL) Always Below 1 Ω
      B22-63 (NSW) - B100-4 (B) Always Below 1 Ω
      B22-99 (P) or B100-3 (PL) - Body ground Always 10 kΩ or higher
      B22-79 (R) or B100-2 (RL) - Body ground Always 10 kΩ or higher
      B22-97 (N) or B100-8 (NL) - Body ground Always 10 kΩ or higher
      B22-81 (D) or B100-7 (DL) - Body ground Always 10 kΩ or higher
      A92-28 (CLL), B100-4 (B), F13-7(ST2) or A58-63(NSW) - Body ground Always 10 kΩ or higher

    OK

    REPLACE ECM Click here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

  8. 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.

    5. According to the display on the GTS, read the Data List.

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

    B

    USE SIMULATION METHOD TO CHECK Click here

    A

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


    1. Disconnect the A92 engine stop and start ECU connector.

    2. Disconnect the B96 neutral position switch connector. (for 1NR-FE)

    3. Disconnect the A100 neutral position switch connector. (for 1KR-FE)

    4. Disconnect the A58 ECM connector.

    5. Disconnect the F13 ignition or starter switch assembly connector.

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

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

      Standard Resistance
      for 1NR-FE
      Tester Connection Condition Specified Condition
      A92-26 (TMVC) - B96-1 (WI) Always Below 1 Ω
      A92-25 (TME2) - B96-3 (F+) Always Below 1 Ω
      A92-27 (TMN) - B96-2 (TMN) Always Below 1 Ω
      A92-26 (TMVC) or B96-1 (WI) - Body ground Always 10 kΩ or higher
      A92-25 (TME2) or B96-3 (F+) - Body ground Always 10 kΩ or higher
      A92-27 (TMN) or B96-2 (TMN) - Body ground Always 10 kΩ or higher
      for 1KR-FE
      Tester Connection Condition Specified Condition
      A92-26 (TMVC) - A100-1 (WI) Always Below 1 Ω
      A92-25 (TME2) - A100-3 (F+) Always Below 1 Ω
      A92-27 (TMN) - A100-2 (TMN) Always Below 1 Ω
      A92-26 (TMVC) or A100-1 (WI) - Body ground Always 10 kΩ or higher
      A92-25 (TME2) or A100-3 (F+) - Body ground Always 10 kΩ or higher
      A92-27 (TMN) or A100-2 (TMN) - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

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


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

      A01VLTPE02
      Text in Illustration
      *a

      Component with harness connected

      (Engine Stop and Start ECU)

      		 - -
      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      A92-27 (TMN) - A92-25 (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
      Result Proceed to
      OK A
      NG (for 1NR-FE) B
      NG (for 1KR-FE) C

    A

    REPLACE ENGINE STOP AND START ECU Click here

    B

    REPLACE NEUTRAL POSITION SWITCH Click here

    C

    REPLACE NEUTRAL POSITION SWITCH Click here