AIR CONDITIONING SYSTEM, Diagnostic DTC:B1418/18

DTC Code DTC Name
B1418/18 Exhaust Gas Sensor Circuit

DESCRIPTION

The smog ventilation sensor is installed to the front of the cooler condenser assembly to automatically control the air inlet mode (fresh, recirculation/fresh, and recirculation).

This sensor detects HC and CO in exhaust gasses and transmits signals to the air conditioning amplifier assembly.

DTC No. Detection Item DTC Detection Condition Trouble Area Memory
B1418/18 Exhaust Gas Sensor Circuit Short in smog ventilation sensor circuit (HC, CO)

  • Smog ventilation sensor

  • Harness or connector

  • Air conditioning amplifier assembly

 -

WIRING DIAGRAM

A01QCCNE01

CAUTION / NOTICE / HINT

Note


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

  • Before disconnecting the cable from the negative (-) battery terminal or replacing the air conditioning amplifier assembly, record the last operation state of the air conditioning for each transmitter. After replacement, it is necessary to perform memory registration for each transmitter.

    Click here

  • If DTCs B1418/18 and B1461/61 are stored simultaneously, there may be a malfunction in the smog ventilation sensor power source related circuits.

PROCEDURE


  1. READ VALUE USING GTS


    1. Connect the GTS to the DLC3.

    2. Turn the engine switch on (IG).

    3. Turn the GTS on.

    4. Enter the following menus: Body Electrical / Air Conditioner / Data List.

    5. Read the Data List according to the display on the GTS.

      Tester Display Measurement Item Range Normal Condition Diagnostic Note
      Emission Gas Sensor Smog ventilation sensor

      Min.: 0

      Max.: 255

      		 Smog ventilation sensor value increases as gas amount increases -
      OK
      The display is as specified in the normal condition column.
      Result
      Result Proceed to
      NG A
      OK (When troubleshooting according to Problem Symptoms Table) B
      OK (When troubleshooting according to the DTC) C

    B

    PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE Click here

    C

    REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY Click here

    A

  2. CHECK HARNESS AND CONNECTOR (SMOG VENTILATION SENSOR - BATTERY AND BODY GROUND)


    1. Disconnect the B7 smog ventilation sensor connector.

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

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      B7-3 (IG) - Body ground Engine switch on (IG) 11 to 14 V
      B7-3 (IG) - Body ground Engine switch off Below 1 V

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      B7-6 (E) - Body ground Always Below 1 Ω
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  3. CHECK HARNESS AND CONNECTOR (SMOG VENTILATION SENSOR - AIR CONDITIONING AMPLIFIER ASSEMBLY)


    1. Disconnect the K65 air conditioning amplifier assembly connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      B7-1 (SG) - K65-32 (SG-2) Always Below 1 Ω
      B7-2 (DGS) - K65-24 (DGS) Always Below 1 Ω
      B7-1 (SG) or K65-32 (SG-2) - Body ground Always 10 kΩ or higher
      B7-2 (DGS) or K65-24 (DGS) - Body ground Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  4. INSPECT SMOG VENTILATION SENSOR


    1. Remove the smog ventilation sensor.

      Click here

    2. Inspect the smog ventilation sensor.

      Click here

      Result
      Proceed to
      OK
      NG

    OK

    REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY Click here

    NG

    REPLACE SMOG VENTILATION SENSOR Click here