AIR CONDITIONING SYSTEM(for Automatic Air Conditioning System) Rear Air Conditioning Relay Circuit

DESCRIPTION

When the No. 2 air conditioning control assembly (rear blower switch) is set to position LO or higher, the contact of the RR A/C relay is closed, current flows to the rear blower motor, and the rear blower motor operates. The rear blower motor speed can be changed by exchanging the ground and the rear blower resistor circuit with the No. 2 air conditioning control assembly (rear blower switch).

WIRING DIAGRAM

B001W2WE02

PROCEDURE


  1. INSPECT FUSE (A/C IG, RR A/C NO.2)


    1. Remove the A/C IG and RR A/C NO. 2 fuses from the cowl side junction block LH.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      A/C IG fuse Always Below 1 Ω
      RR A/C NO. 2 fuse Always Below 1 Ω

    NG

    REPLACE FUSE

    OK

  2. INSPECT RR A/C RELAY

    B001XSYE22

    1. Remove the RR A/C relay from the engine room relay block.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      3 - 4 Battery voltage is not applied between terminals 1 and 2 Below 1 Ω
      3 - 5 Battery voltage is not applied between terminals 1 and 2 10 kΩ or higher
      3 - 4 Battery voltage is applied to terminals 1 and 2 10 kΩ or higher
      3 - 5 Battery voltage is applied to terminals 1 and 2 Below 1 Ω

    NG

    REPLACE RR A/C RELAY

    OK

  3. INSPECT REAR BLOWER MOTOR

    B001ZPBE01

    1. Disconnect the z49 motor connector.

    2. Connect the battery's positive (+) lead to terminal 2 and the negative (-) lead to terminal 1, then check that the rear blower motor operates smoothly.

      OK
      The rear blower motor operates smoothly.

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

      Standard Current
      Tester Connection Condition Specified Condition
      z49-1 (-) - z49-2 (+) Rear blower motor operates 1 to 3 A

    NG

    REPLACE REAR BLOWER MOTOR Click here

    OK

  4. INSPECT NO. 2 AIR CONDITIONING CONTROL ASSEMBLY (REAR BLOWER SWITCH)

    B001W25E02
    *1 Component without harness connected: (No. 2 Air Conditioning Control Assembly)

    1. Remove the No. 2 air conditioning control assembly Click here.

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      ALL - E89-6 (E) OFF 10 kΩ or higher
      E89-5 (LO) - E89-6 (E) LO Below 1 Ω
      E89-3 (M1) - E89-6 (E) M1 Below 1 Ω
      E89-4 (M2) - E89-6 (E) M2 Below 1 Ω
      E89-8 (HI) - E89-6 (E) HI Below 1 Ω

    NG

    REPLACE NO. 2 AIR CONDITIONING CONTROL ASSEMBLY Click here

    OK

  5. INSPECT REAR BLOWER RESISTOR

    B001WWSE01
    *1 Component without harness connected: (Rear Blower Resistor)

    1. Remove the rear blower resistor Click here.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      z52-1 (HI) - z52-2 (M1) Always 1.32 to 1.52 Ω
      z52-1 (HI) - z52-3 (M2) Always 0.39 to 0.45 Ω
      z52-1 (HI) - z52-4 (LO) Always 2.24 to 2.4 Ω

    NG

    REPLACE REAR BLOWER RESISTOR Click here

    OK

  6. CHECK REAR COOLING UNIT EXPANSION VALVE (OPERATION)


    1. Replace the rear cooling unit expansion valve Click here.

      Tech Tips

      Since the rear cooling unit expansion valve cannot be inspected while it is removed from the vehicle, replace the rear cooling unit expansion valve with a normal one and check that the condition returns to normal.

      OK
      Same problem does not occur.

    OK

    CHECK REAR COOLING UNIT EXPANSION VALVE Click here

    NG

  7. CHECK HARNESS AND CONNECTOR (REAR BLOWER RESISTOR - WIRING AIR CONDITIONING HARNESS)

    B001ZBAE01
    *1 Front view of wire harness connector: (to Wiring Air Conditioning Harness Sub-assembly)
    *2 Front view of wire harness connector: (to Rear Blower Resistor)

    1. Disconnect the wiring air conditioning harness sub-assembly connector.

    2. Disconnect the z52 rear blower resistor connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      6 (M1) - z52-2 (M1) Always Below 1 Ω
      5 (M2) - z52-3 (M2) Always Below 1 Ω
      4 (HI) - z52-1 (HI) Always Below 1 Ω
      7 (LO) - z52-4 (LO) Always Below 1 Ω

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  8. CHECK HARNESS AND CONNECTOR (REAR BLOWER SWITCH - WIRING AIR CONDITIONING HARNESS)

    B001YS5E01
    *1 Front view of wire harness connector: (to No. 2 Air Conditioning Control Assembly)
    *2 Front view of wire harness connector: (to Wiring Air Conditioning Harness Sub-assembly)

    1. Disconnect the E89 No. 2 air conditioning control assembly connector.

    2. Disconnect the Wiring air conditioning harness sub-assembly connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      E89-3 (M1) - 6 (M1) Always Below 1 Ω
      E89-4 (M2) - 5 (M2) Always Below 1 Ω
      E89-8 (HI) - 4 (HI) Always Below 1 Ω
      E89-5 (LO) - 7 (LO) Always Below 1 Ω
      E89-6 (E) - Body ground Always Below 1 Ω

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  9. CHECK HARNESS AND CONNECTOR (REAR BLOWER RESISTOR - REAR BLOWER MOTOR)

    B001XL5E02
    *1 Front view of wire harness connector: (to Rear Blower Resistor)
    *2 Front view of wire harness connector: (to Rear Blower Motor)

    1. Disconnect the z52 rear blower resistor connector.

    2. Disconnect the z49 rear motor connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      z52-1 (HI) - z49-1 Always Below 1 Ω

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  10. CHECK HARNESS AND CONNECTOR (REAR BLOWER MOTOR - BODY GROUND AND BATTERY)

    B001W51E02
    *1 Front view of wire harness connector: (to Rear Blower Motor)

    1. Disconnect the z49 rear motor connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      z49-2 - Body ground Always Below 1 Ω

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

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      z49-2 - Body ground

      Engine switch on (IG)

      Heater control (blower switch) HI

      		 11 to 14 V

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  11. CHECK HARNESS AND CONNECTOR (AIR CONDITIONING AMPLIFIER - BATTERY AND BODY GROUND)

    B001ZR1E02
    *1 Rear view of wire harness connector: (to Air Conditioning Amplifier Assembly)
    *2 RCRL

    1. Disconnect the E81air conditioning amplifier connector.

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

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      E81-18 (RCRL) - Body ground

      Engine switch on (IG)

      Heater control (blower switch): OFF

      		 11 to 14 V
      E81-18 (RCRL) - Body ground

      Engine switch on (IG)

      Heater control (blower switch): ON

      		 Below 1 V

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      E81-14 (GND) - Body ground Always Below 1 Ω

    OK

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

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR