AIR CONDITIONING SYSTEM(for Automatic Air Conditioning System) PTC Heater Circuit

DTC Code DTC Name
PTC Heater Circuit

DESCRIPTION

The air conditioning amplifier assembly sends operation signals to the PTC heater relays when quick heater assembly operation conditions are met. Based on the signals from the air conditioning amplifier assembly, the PTC heater relays turn on, and power is supplied to the quick heater assembly installed in the air conditioning radiator assembly.

Table 1. Quick Heater Assembly Operation Condition

Control ECU

Condition

Air Conditioning Amplifier Assembly

Engine running

Combination switch assembly (ECO mode switch) off

Blower motor on

Temperature set to MAX HOT

IDH terminal signal below 1 V

(Inverter with converter assembly overload not detected)

  • Engine coolant temperature 65°C or less (3 heaters operate)

  • Engine coolant temperature 70°C or less (2 heaters operate)

  • Engine coolant temperature 75°C or less (A heater operates)

Ambient temperature 10°C or less

WIRING DIAGRAM

E269929E01
E269936E02
E269936E07

CAUTION / NOTICE / HINT

Note:

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

PROCEDURE

  1. PERFORM ACTIVE TEST USING GTS

    1. Connect the GTS to the DLC3.

    2. Turn the ignition switch to ON.

    3. Turn the GTS on.

    4. Enter the following menus: Body Electrical / Air Conditioner / Active Test.

    5. Check the operation by referring to the table below.

      Body Electrical > Air Conditioner > Active Test

      Tester Display

      Measurement Item

      Control Range

      Diagnostic Note

      Heater Active Level

      Quick heater assembly

      Min.: 0, Max.: 3

      -

      Body Electrical > Air Conditioner > Active Test

      Tester Display

      Heater Active Level

    Result

    Proceed to

    Heater Active Level changes normally

    Heater Active Level does not change normally

    Heater Active Level does not change normally

    PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE

    Heater Active Level changes normally
  2. INSPECT PTC HEATER RELAY

    1. for Diesel not in Cold Areas (w/o Side Marker Light):

      E269960C01

      *1

      PTC HTR NO.2 Relay

      *2

      PTC HTR NO.1 Relay, PTC HTR NO.3 Relay

      1. Remove the PTC heater relays from the No. 2 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 - 5

        Battery voltage is not applied between terminals 1 and 2

        10 kΩ or higher

        3 - 5

        Battery voltage is applied between terminals 1 and 2

        Below 1 Ω

    2. for Gasoline, Diesel in Cold Areas (w/o Side Marker Light):

      E269961C01

      *1

      PTC HTR NO.2 Relay

      *2

      PTC HTR NO.1 Relay

      1. Remove the PTC heater relays from the No. 2 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 - 5

        Battery voltage is not applied between terminals 1 and 2

        10 kΩ or higher

        3 - 5

        Battery voltage is applied between terminals 1 and 2

        Below 1 Ω

    3. E222294C16

      *1

      PTC HTR NO.2 Relay

      PTC HTR NO.1 Relay

      w/ Side Marker Light:

      1. Remove the PTC heater relays from the No. 2 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 - 5

        Battery voltage is not applied between terminals 1 and 2

        10 kΩ or higher

        3 - 5

        Battery voltage is applied between terminals 1 and 2

        Below 1 Ω

    Result

    Proceed to

    OK

    NG

    NG

    REPLACE PTC HEATER RELAY

    OK
  3. CHECK HARNESS AND CONNECTOR (PTC HEATER RELAY - BATTERY)

    1. E269962C01

      *1

      No. 2 Engine Room Relay Block

      *2

      PTC HTR NO.1 Relay

      *3

      PTC HTR NO.2 Relay

      *4

      PTC HTR NO.3 Relay

      for Diesel not in Cold Areas (w/o Side Marker Light):

      1. Remove the PTC heater relays from the No. 2 engine room relay block.

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

        Standard Voltage

        PTC HTR NO.1

        Tester Connection

        Condition

        Specified Condition

        5 - Body ground

        Always

        11 to 14 V

        2 - Body ground

        Ignition switch off

        Below 1 V

        Ignition switch ON

        11 to 14 V

        PTC HTR NO.2

        Tester Connection

        Condition

        Specified Condition

        5 - Body ground

        Always

        11 to 14 V

        1 - Body ground

        Ignition switch off

        Below 1 V

        Ignition switch ON

        11 to 14 V

        PTC HTR NO.3

        Tester Connection

        Condition

        Specified Condition

        5 - Body ground

        Always

        11 to 14 V

        2 - Body ground

        Ignition switch off

        Below 1 V

        Ignition switch ON

        11 to 14 V

    2. E269963C01

      *1

      No. 2 Engine Room Relay Block

      *2

      PTC HTR NO.1 Relay

      *3

      PTC HTR NO.2 Relay

      for Gasoline, Diesel in Cold Areas (w/o Side Marker Light):

      1. Remove the PTC heater relays from the No. 2 engine room relay block.

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

        Standard Voltage

        PTC HTR NO.1

        Tester Connection

        Condition

        Specified Condition

        5 - Body ground

        Always

        11 to 14 V

        2 - Body ground

        Ignition switch off

        Below 1 V

        Ignition switch ON

        11 to 14 V

        PTC HTR NO.2

        Tester Connection

        Condition

        Specified Condition

        5 - Body ground

        Always

        11 to 14 V

        1 - Body ground

        Ignition switch off

        Below 1 V

        Ignition switch ON

        11 to 14 V

    3. E271244C01

      *1

      PTC HTR NO.1 Relay

      *2

      PTC HTR NO.2 Relay

      *a

      Component without relay installed

      (No. 2 Engine Room Relay Block)

      w/ Side Marker Light:

      1. Remove the PTC heater relays from the No. 2 engine room relay block.

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

        Standard Voltage

        PTC HTR NO.1

        Tester Connection

        Condition

        Specified Condition

        5 - Body ground

        Always

        11 to 14 V

        2 - Body ground

        Ignition switch off

        Below 1 V

        Ignition switch ON

        11 to 14 V

        PTC HTR NO.2

        Tester Connection

        Condition

        Specified Condition

        5 - Body ground

        Always

        11 to 14 V

        2 - Body ground

        Ignition switch off

        Below 1 V

        Ignition switch ON

        11 to 14 V

    Result

    Proceed to

    OK

    NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK
  4. CHECK HARNESS AND CONNECTOR (PTC HEATER RELAY - AIR CONDITIONING AMPLIFIER ASSEMBLY)

    1. for Diesel not in Cold Areas (w/o Side Marker Light):

      1. Disconnect the G81 air conditioning amplifier assembly connector.

      2. Remove the PTC heater relays from the No. 2 engine room relay block.

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

        Standard Resistance

        Tester Connection

        Condition

        Specified Condition

        1 - G81-40 (PTC1)

        Always

        Below 1 Ω

        2 - G81-3 (PTC2)

        Always

        Below 1 Ω

        1 - G81-39 (PTC3)

        Always

        Below 1 Ω

        G81-40 (PTC1) - Body ground

        Always

        10 kΩ or higher

        G81-3 (PTC2) - Body ground

        Always

        10 kΩ or higher

        G81-39 (PTC3) - Body ground

        Always

        10 kΩ or higher

    2. for Gasoline, Diesel in Cold Areas (w/o Side Marker Light):

      1. Disconnect the G81 air conditioning amplifier assembly connector.

      2. Remove the PTC heater relays from the No. 2 engine room relay block.

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

        Standard Resistance

        Tester Connection

        Condition

        Specified Condition

        1 - G81-40 (PTC1)

        Always

        Below 1 Ω

        2 - G81-3 (PTC2)

        Always

        Below 1 Ω

        G81-40 (PTC1) - Body ground

        Always

        10 kΩ or higher

        G81-3 (PTC2) - Body ground

        Always

        10 kΩ or higher

    3. w/ Side Marker Light:

      1. Disconnect the G81 air conditioning amplifier assembly connector.

      2. Remove the PTC heater relays from the No. 2 engine room relay block.

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

        Standard Resistance

        Tester Connection

        Condition

        Specified Condition

        1 - G81-40 (PTC1)

        Always

        Below 1 Ω

        1 - G81-3 (PTC2)

        Always

        Below 1 Ω

        G81-40 (PTC1) - Body ground

        Always

        10 kΩ or higher

        G81-3 (PTC2) - Body ground

        Always

        10 kΩ or higher

    Result

    Proceed to

    OK

    NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK
  5. CHECK HARNESS AND CONNECTOR (PTC HEATER RELAY - QUICK HEATER ASSEMBLY)

    1. for Diesel not in Cold Areas (w/o Side Marker Light):

      1. Remove the PTC heater relays from the No. 2 engine room relay block.

      2. Disconnect the A31 quick heater assembly connector.

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

        Standard Resistance

        PTC HTR NO.1

        Tester Connection

        Condition

        Specified Condition

        3 - A31-1 (B)

        Always

        Below 1 Ω

        A31-1 (B) - Body ground

        Always

        10 kΩ or higher

        PTC HTR NO.2

        Tester Connection

        Condition

        Specified Condition

        3 - A31-2 (B)

        Always

        Below 1 Ω

        A31-2 (B) - Body ground

        Always

        10 kΩ or higher

        PTC HTR NO.3

        Tester Connection

        Condition

        Specified Condition

        3 - A31-3 (B)

        Always

        Below 1 Ω

        A31-3 (B) - Body ground

        Always

        10 kΩ or higher

    2. for Gasoline, Diesel in Cold Areas (w/o Side Marker Light):

      1. Remove the PTC heater relays from the No. 2 engine room relay block.

      2. Disconnect the A31 quick heater assembly connector.

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

        Standard Resistance

        PTC HTR NO.1

        Tester Connection

        Condition

        Specified Condition

        3 - A31-1 (B)

        Always

        Below 1 Ω

        A31-1 (B) - Body ground

        Always

        10 kΩ or higher

        PTC HTR NO.2

        Tester Connection

        Condition

        Specified Condition

        3 - A31-3 (B)

        Always

        Below 1 Ω

        A31-3 (B) - Body ground

        Always

        10 kΩ or higher

    3. w/ Side Marker Light:

      1. Remove the PTC heater relays from the No. 2 engine room relay block.

      2. Disconnect the A31 quick heater assembly connector.

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

        Standard Resistance

        PTC HTR NO.1

        Tester Connection

        Condition

        Specified Condition

        3 - A31-1 (B)

        Always

        Below 1 Ω

        A31-1 (B) - Body ground

        Always

        10 kΩ or higher

        PTC HTR NO.2

        Tester Connection

        Condition

        Specified Condition

        3 - A31-3 (B)

        Always

        Below 1 Ω

        A31-3 (B) - Body ground

        Always

        10 kΩ or higher

    Result

    Proceed to

    OK

    NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK
  6. CHECK HARNESS AND CONNECTOR (QUICK HEATER ASSEMBLY - BODY GROUND)

    1. for Diesel not in Cold Areas (w/o Side Marker Light):

      1. Disconnect the A30 and A35 quick heater assembly connectors.

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

        Standard Resistance

        Tester Connection

        Condition

        Specified Condition

        A30-1 (E) - Body ground

        Always

        Below 1 Ω

        A35-1 (E) - Body ground

        Always

        Below 1 Ω

    2. for Gasoline, Diesel in Cold Areas (w/o Side Marker Light):

      1. Disconnect the A32 quick heater assembly connector.

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

        Standard Resistance

        Tester Connection

        Condition

        Specified Condition

        A32-1 (E) - Body ground

        Always

        Below 1 Ω

        A32-2 (E) - Body ground

        Always

        Below 1 Ω

    3. w/ Side Marker Light:

      1. Disconnect the A32 quick heater assembly connector.

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

        Standard Resistance

        Tester Connection

        Condition

        Specified Condition

        A32-1 (E) - Body ground

        Always

        Below 1 Ω

        A32-2 (E) - Body ground

        Always

        Below 1 Ω

    Result

    Proceed to

    OK

    NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK
  7. INSPECT QUICK HEATER ASSEMBLY

    1. Remove the quick heater assembly.

      Click here

    2. Inspect the quick heater assembly.

      Click here

    Result

    Proceed to

    OK

    NG

    OK

    REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY

    NG

    REPLACE QUICK HEATER ASSEMBLY