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 Code DTC Detection Condition Trouble Area
B1418/18 Open or short in smog ventilation sensor circuit (HC, CO)

  • Smog ventilation sensor

  • Harness or connector

  • Air conditioning amplifier assembly

WIRING DIAGRAM

B001B4AE07

CAUTION / NOTICE / HINT

Note


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

  • 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 (EMISSION GAS SENSOR)


    1. Use the Data List to check if the smog ventilation sensor is functioning properly Click here.

      Air Conditioner
      Tester Display Measurement Item / Range Normal Condition Diagnostic Note
      Emission Gas Sensor

      Smog ventilation sensor /

      Min.: 0, Max.: 255

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

    A

    REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY Click here

    B

    PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE Click here

    C

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


    1. B0019R8E02
      Text in Illustration
      *a

      Front view of wire harness connector

      (to Smog Ventilation Sensor)

      Disconnect the A45 smog ventilation sensor connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      A45-6 (E) - Body ground Always Below 1 Ω

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

      Standard Voltage
      Tester Connection Condition Specified Condition
      A45-3 (IG) - Body ground Engine switch off Below 1 V
      A45-3 (IG) - Body ground Engine switch on (IG) 11 to 14 V

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  3. INSPECT SMOG VENTILATION SENSOR


    1. Remove the smog ventilation sensor Click here.

    2. Inspect the smog ventilation sensor Click here.


    NG

    REPLACE SMOG VENTILATION SENSOR Click here

    OK

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


    1. Disconnect the A45 smog ventilation sensor connector.

    2. Disconnect the E35 air conditioning amplifier assembly connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      A45-1 (SG) - E35-32 (SG-2) Always Below 1 Ω
      A45-2 (DGS) - E35-24 (DGS) Always Below 1 Ω
      A45-1 (SG) or E35-32 (SG-2) - Body ground Always 10 kΩ or higher
      A45-2 (DGS) or E35-24 (DGS) - Body ground Always 10 kΩ or higher
      E35-30 (SG-4) - E35-24 (DGS) Always 10 kΩ or higher

    OK

    REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY Click here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR