СИСТЕМА ECD Air Conditioning Signal Circuit

DESCRIPTION

When the A/C compressor is on, the A/C amplifier sends the A/C signal to the ECM and the ECM increases the fuel injection volume to improve driveability during engine idling.

WIRING DIAGRAM

B001FT9E09
*1 A/C ECU

PROCEDURE


  1. READ VALUE USING GTS (AIR CONDITIONING SIGNAL)


    1. Connect the GTS to the DLC3.

    2. Start the engine.

    3. Turn the A/C switch on.

    4. Enter the following menus: Powertrain / Engine and ECT / Data List / A/C SIG.

      Result
      Switch Condition A/C SIG
      A/C switch off OFF
      A/C switch on ON

    OK

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

    NG

  2. CHECK ECM (AC1 VOLTAGE)


    1. B001HEDE02
      Text in Illustration
      *a

      Component with harness connected

      (ECM)

      Start the engine.

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

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      G182-34 (AC1) - Body ground A/C switch on Below 1.5 V
      G182-34 (AC1) - Body ground A/C switch off 7.5 to 14 V

    OK

    REPLACE ECM Click here

    NG

  3. CHECK HARNESS AND CONNECTOR (ECM - AIR CONDITIONING AMPLIFIER)


    1. Disconnect the A/C amplifier connector.

    2. Disconnect the ECM connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      G25-17 (AC1) - G182-34 (AC1) Always Below 1 Ω
      G25-17 (AC1) or G182-34 (AC1) - Body ground Always 10 kΩ or higher

    4. Reconnect the A/C amplifier connector.

    5. Reconnect the ECM connector.


    OK

    REPLACE AIR CONDITIONING AMPLIFIER Click here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR