AUTOMATIC TRANSAXLE SYSTEM, Diagnostic DTC:P079112, P079114, P079131

DTC Code DTC Name
P079112 Intermediate Shaft Speed Sensor "A" Circuit Short to Battery
P079114 Intermediate Shaft Speed Sensor "A" Circuit Short to Ground or Open
P079131 Intermediate Shaft Speed Sensor "A" No Signal

DESCRIPTION

The output speed sensor NC detects the rotation speed of the counter gear, which indicates the intermediate shaft revolution (speed) of the transaxle. By comparing the input speed sensor NT signal to the output speed sensor NC signal, the ECM detects the shift timing of the gears and appropriately controls the engine torque and hydraulic pressure according to various conditions, thus, providing smooth gear shifts.

DTC No. Detection Item DTC Detection Condition Trouble Area MIL Memory Note
P079112 Intermediate Shaft Speed Sensor "A" Circuit Short to Battery

1. Diagnosis Condition 2. Malfunction Status 3. Malfunction Time 4. Other


  1. The battery voltage is 8 V or more, the engine switch is on (IG) and the starter is off.

  2. The output speed sensor NC input voltage is more than 1.9 V.

  3. 2 seconds

  4. 1-trip detection logic

  • Harness and connector

  • Wiring harness connector

  • Transmission wire

  • Output speed sensor NC (transmission revolution sensor)

  • ECM

 Comes on DTC stored

SAE Code:

P07C6
P079114 Intermediate Shaft Speed Sensor "A" Circuit Short to Ground or Open

1. Diagnosis Condition 2. Malfunction Status 3. Malfunction Time 4. Other


  1. The battery voltage is 8 V or more, the engine switch is on (IG) and the starter is off.

  2. The output speed sensor NC input voltage is less than 0.1 V.

  3. 2 seconds

  4. 1-trip detection logic

  • Harness and connector

  • Wiring harness connector

  • Transmission wire

  • Output speed sensor NC (transmission revolution sensor)

  • ECM

 Comes on DTC stored

SAE Code:

P07C5
P079131 Intermediate Shaft Speed Sensor "A" No Signal

1. Diagnosis Condition 2. Malfunction Status 3. Malfunction Time 4. Other


  1. The vehicle is being driven with the shift lever in D at vehicle speed of 25 km/h (16 mph) or more.

  2. The speed indicated by the output speed sensor NC signal is less than 300 rpm.

  3. 2 seconds

  4. 1-trip detection logic

  • Harness and connector

  • Wiring harness connector

  • Transmission wire

  • Output speed sensor NC (transmission revolution sensor)

  • ECM

 Comes on DTC stored

SAE Code:

P0793

MONITOR DESCRIPTION

The NT terminal of the ECM detects a revolution signal from the input speed sensor NT (input RPM). The ECM calculates gear shifts by comparing the input speed sensor NT signal to the output speed sensor NC signal.

While the vehicle is being driven in 2nd, 3rd, 4th or 5th gear with the shift lever in D, if the input shaft revolution (speed) is less than 300 rpm*1 and the output shaft revolution (speed) is more than 1000 rpm*2, the ECM interprets this as a malfunction, illuminates the MIL and stores a DTC.

*1: Pulse is not output or is irregularly output.

*2: The vehicle speed is 50 km/h (31 mph) or more.

WIRING DIAGRAM

Refer to DTC P071512.

Click here

CAUTION / NOTICE / HINT

Note

Perform registration and/or initialization when parts related to the automatic transaxle are replaced.

Click here

Tech Tips

After performing repair, clear the DTCs and perform the following procedure to check that DTCs are not output.


  1. Perform the D Position Shift Test in Road Test inspection and drive the vehicle for 2 seconds or more at 25 km/h (16 mph) or more.

    Click here

  2. Check for DTCs again.

    Click here


  1. DATA LIST

    Tech Tips

    Using the GTS to read the Data List allows the values or states of switches, sensors, actuators and other items to be read without removing any parts. This non-intrusive inspection can be very useful because intermittent conditions or signals may be discovered before parts or wiring is disturbed. Reading the Data List information early in troubleshooting is one way to save diagnostic time.

    Note

    In the table below, the values listed under "Normal Condition" are reference values. Do not depend solely on these reference values when deciding whether a part is faulty or not.


    1. Warm up the engine.

    2. Turn the engine switch off.

    3. Connect the GTS to the DLC3.

    4. Turn the engine switch on (IG).

    5. Turn the GTS on.

    6. Enter the following menus: Powertrain / Transmission / Data List.

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


      Powertrain > Transmission > Data List
      Tester Display Measurement Item Range Normal Condition Diagnostic Note
      NC Sensor Speed Counter gear speed

      Min.: 0 rpm

      Max.: 12750 rpm

      		 0 rpm: Vehicle stopped Data is displayed in increments of 50 rpm.

      Powertrain > Transmission > Data List
      Tester Display
      NC Sensor Speed

      Tech Tips


      • NC Sensor Speed is always 0 while driving: Open or short in the sensor or circuit.

      • NC Sensor Speed is always more than 0 and less than 300 rpm while driving the vehicle at 50 km/h (31 mph) or more: Sensor malfunction, improper installation, or intermittent connection malfunction in the circuit.

PROCEDURE


  1. INSPECT TRANSMISSION REVOLUTION SENSOR INSTALLATION


    1. Remove the transmission valve body assembly.

      Click here

    2. A01VTLM

      Make sure that the connector is properly connected, and check the transmission revolution sensor installation condition.

      OK
      The installation bolts are tightened properly and there is no clearance between the transmission revolution sensor and transmission valve body assembly.
      Result
      Proceed to
      OK
      NG

    NG

    REINSTALL OR REPLACE TRANSMISSION REVOLUTION SENSOR Click here

    OK

  2. INSPECT TRANSMISSION WIRE


    1. A01VU2AC12
      *a

      Component without harness connected

      (Transmission Wire)
      *b Transmission Revolution Sensor Side
      *c Wiring Harness Connector Side

      Disconnect the transmission revolution sensor connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      NCB transmission revolution sensor side - A-4 (NCB) Always Below 1 Ω
      NCO transmission revolution sensor side - A-3 (NCO) Always Below 1 Ω
      NCB transmission revolution sensor side or A-4 (NCB) - Body ground (transmission valve body assembly) and other terminals Always 10 kΩ or higher
      NCO transmission revolution sensor side or A-3 (NCO) - Body ground (transmission valve body assembly) and other terminals Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    NG

    REPLACE TRANSMISSION WIRE Click here

    OK

  3. CHECK HARNESS AND CONNECTOR (WIRING HARNESS CONNECTOR - ECM)


    1. Disconnect the D57 wiring harness connector connector.

    2. Disconnect the D1 ECM connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      D57-4 (NCB) - D1-73 (NCB) Always Below 1 Ω
      D57-3 (NCO) - D1-74 (NCO) Always Below 1 Ω
      D57-4 (NCB) or D1-73 (NCB) - Body ground and other terminals Always 10 kΩ or higher
      D57-3 (NCO) or D1-74 (NCO) - Body ground and other terminals Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  4. INSPECT WIRING HARNESS CONNECTOR


    1. Remove the wiring harness connector.

      A01VXDLC22
      *1 Wiring Harness Connector - -
      *a Transmission Wire Side *b ECM Side

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      A-4 (NCB) - D57-4 (NCB) Always Below 1 Ω
      A-3 (NCO) - D57-3 (NCO) Always Below 1 Ω
      A-4 (NCB) - All other terminals except D57-4 (NCB) Always 10 kΩ or higher
      A-3 (NCO) - All other terminals except D57-3 (NCO) Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    NG

    REPLACE WIRING HARNESS CONNECTOR Click here

    OK

  5. REPLACE TRANSMISSION REVOLUTION SENSOR


    1. Replace the transmission revolution sensor.

      Click here

      Result
      Proceed to
      NEXT

    NEXT

  6. CHECK IF DTC OUTPUT RECURS (DTC P079112, P079114 AND/OR P079131)


    1. Connect the GTS to the DLC3.

    2. Start the engine and turn the GTS on.

    3. Clear the DTCs.

      Click here

      Tech Tips

      Write down the currently output DTCs before clearing them.


      Powertrain > Transmission > Clear DTCs

    4. Perform the monitor drive pattern.

      Click here

    5. Enter the following menus: Powertrain / Transmission / Trouble Codes.


      Powertrain > Transmission > Trouble Codes

    6. Read the DTCs using the GTS.

      Result
      Result Proceed to
      DTC P079112, P079114 and/or P079131 is output A
      DTCs are not output B

    A

    REPLACE ECM Click here

    B

    END