Click here

AIR CONDITIONING SYSTEM PTC Heater Circuit

Click here
Click here
DTC Code DTC Name
  PTC Heater Circuit
Click here

DESCRIPTION

The air conditioning amplifier assembly sends operation signals to the PTC HTR relays when quick heater assembly operation conditions are met. Based on the signals from the air conditioning amplifier assembly, the PTC HTR 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 Blower motor on
Temperature set to MAX HOT
ECO mode switch (integration control and panel assembly) off

IDH terminal signal less than 1 V

(Inverter with converter assembly overload not detected)
Engine coolant temperature 70°C or lower
Ambient temperature 10°C or lower
Click here

WIRING DIAGRAM

Click here

CAUTION / NOTICE / HINT

Note:

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

Click here

PROCEDURE


  1. Click here

    PERFORM ACTIVE TEST USING GTS


    1. Connect the GTS to the DLC3.

    2. Turn the power switch on (IG).

    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.

      Table 2. Air Conditioner
      Tester Display Test Part Control Range Diagnostic Note
      Heater Active Level Quick heater assembly Min.: 0, Max.: 2 -
      OK
      Heater Active Level changes normally.

  2. Click here

    INSPECT PTC HEATER RELAY (PTC HTR NO. 1, PTC HTR NO. 2)


    1. A0004ZQE25

      Remove the PTC HTR NO. 1 relay and PTC HTR NO. 2 relay.

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

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

  3. Click here

    CHECK HARNESS AND CONNECTOR (PTC HTR NO. 1 RELAY, PTC HTR NO. 2 RELAY - POWER SOURCE)


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

      Standard Voltage
      Table 3. PTC1
      Tester Connection Condition Specified Condition
      3 - Body ground Power switch off 11 to 14 V
      2 - Body ground Power switch on (IG) 11 to 14 V
      Table 4. PTC2
      Tester Connection Condition Specified Condition
      3 - Body ground Power switch off 11 to 14 V
      2 - Body ground Power switch on (IG) 11 to 14 V

    • OKClick here
    • NG

      REPAIR OR REPLACE HARNESS OR CONNECTOR

  4. Click here

    CHECK HARNESS AND CONNECTOR (PTC HTR NO. 1 RELAY, PTC HTR NO. 2 RELAY - AIR CONDITIONING AMPLIFIER ASSEMBLY)


    1. Disconnect the H54 air conditioning amplifier assembly connector.

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

      Standard Resistance
      Table 5. PTC1
      Tester Connection Condition Specified Condition
      1 - H54-40 (PTC1) Always Below 1 Ω
      1 - Body ground Always 10 kΩ or higher
      Table 6. PTC2
      Tester Connection Condition Specified Condition
      1 - H54-3 (PTC2) Always Below 1 Ω
      1 - Body ground Always 10 kΩ or higher

    • OKClick here
    • NG

      REPAIR OR REPLACE HARNESS OR CONNECTOR

  5. Click here

    CHECK HARNESS AND CONNECTOR (PTC HTR NO. 1 RELAY, PTC HTR NO. 2 RELAY - QUICK HEATER ASSEMBLY)


    1. Disconnect the H31 quick heater assembly connector.

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

      Standard Resistance
      Table 7. PTC1
      Tester Connection Condition Specified Condition
      5 - H31-1 (B) Always Below 1 Ω
      5 - Body ground Always 10 kΩ or higher
      Table 8. PTC2
      Tester Connection Condition Specified Condition
      5 - H31-2 (B) Always Below 1 Ω
      5 - Body ground Always 10 kΩ or higher

    • OKClick here
    • NG

      REPAIR OR REPLACE HARNESS OR CONNECTOR

  6. Click here

    INSPECT QUICK HEATER ASSEMBLY


    1. Remove the quick heater assembly (Click here).

    2. A0007ZPE01

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      H31-1 (B)- Ground terminal Always Below 1 Ω
      H31-2 (B)- Ground terminal Always Below 1 Ω
      Table 9. Text in Illustration
      *a

      Component without harness connected

      (Quick Heater Assembly)

    • OK

      REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY (Click here)

    • NG

      REPLACE QUICK HEATER ASSEMBLY (Click here)