Code No. P081D: Neutral Position Switch Circuit


OPERATION



  • The power voltage is supplied to the neutral position switch connector terminal from the ETACS-ECU connector terminal +B1.
  • The ON/OFF signal is inputted to the AS&G-ECU connector terminal NTSW from the neutral position switch connector terminal.

FUNCTION



  • The AS&G-ECU detects the gearshift lever position by using the signals of the neutral position switch.
  • In response to the signal, the AS&G-ECU controls the AS&G system.

TROUBLE JUDGMENT


Check Conditions
  • Ignition switch is "ON" position.
  • The diagnosis code No. P0833 is not detected.
  • Ambient temperature is more than -5°C
  • The diagnosis code No. U0141 is not detected.
  • The diagnosis code No. U0100 is not detected.
Judgement Criterion
  • When you drive the vehicle at more than 60 km/h at least one time, the ON/OFF signal of the neutral position switch does not change even once although the ON/OFF signal of the clutch interlock switch is detected more than 10 times.

FAIL-SAFE AND BACKUP FUNCTION



  • In the normal operation, the auto stop is prohibited.

PROBABLE CAUSES



  • Open/short circuit or harness damage in neutral position switch circuit or loose connector contact
  • Failed neutral position switch
  • Failed installation of neutral position switch
  • Failed system inside transmission
  • Failed AS&G-ECU

DIAGNOSIS PROCEDURE

STEP 1. M.U.T.-III data list

  • Refer to Data List Reference Table .

  1. item 8: Neutral position switch

Q. Is the check result normal?
Intermittent malfunction (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunctions ).
Go to Step 2.

STEP 2. Continuity check on B-129 neutral position switch connector.

  • Disconnect connector, and check at switch side.
  • Continuity check between terminals.
OK:
    Continuity (Gearshift lever position: Neutral)
    No continuity (Gearshift lever position: Except neutral)

Q. Is the check result normal?
Go to Step 5.
Go to Step 3.

STEP 3. Check the installation state of the neutral position switch.

Q. Is the check result normal?
Go to Step 4.
Repair.

STEP 4. Check the neutral position switch itself.

  • Check the neutral position switch itself (Refer to GROUP 22A - On-vehicle service - Neutral Position Switch Check ).

Q. Is the check result normal?
The area affecting the neutral position switch inside the transmission can possibly be abnormal. Overhaul and repair the transmission, or change the transmission.
Replace the neutral position switch.

STEP 5. Perform voltage measurement at B-129 neutral position switch connector.

  • Disconnect connector, and measure at harness side.
  • Ignition switch: ON
  • Voltage between terminal ETACS-ECU +B1 terminal and earth.
OK: System voltage

Q. Is the check result normal?
Go to Step 6.
Repair the connector(s), or check short to earth, and open circuit in +B1 line between ETACS-ECU connector and neutral position switch connector.

STEP 6. Check of harness damage in +B1 line between ETACS-ECU connector and neutral position switch connector.

Q. Is the check result normal?
Go to Step 7.
Repair the connector(s) or wiring harness.

STEP 7. Check of short to earth, open circuit and harness damage in NTSW line between neutral position switch connector and AS&G-ECU connector.

  • Check output line for open/short circuit and damage.

Q. Is the check result normal?
Go to Step 8.
Repair the damaged harness wire.

STEP 8. M.U.T.-III diagnosis code

  • Reconfirmation of the diagnosis code.

Q. Is the diagnosis code set?
Replace the AS&G-ECU.
Intermittent malfunction (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunctions ).