AIR CONDITIONING SYSTEM Heater Water Pump Circuit

DTC Code DTC Name
Heater Water Pump Circuit

DESCRIPTION

The heater accessory assembly sends engine coolant to the heater core assembly while the engine is stopped to prevent heater effectiveness from becoming low. Directed by the air conditioning amplifier assembly, the hybrid vehicle control ECU operates the A/C W/PMP relay and drives the heater accessory assembly.

WIRING DIAGRAM

E337654E02

CAUTION / NOTICE / HINT

Note:

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

PROCEDURE

  1. CHECK CAN COMMUNICATION SYSTEM

    1. Using the GTS, check if the CAN communication system is functioning normally.

      OK

      CAN communication system DTCs are not output.

    Result

    Proceed to

    OK

    NG
    NG

    GO TO CAN COMMUNICATION SYSTEM

    OK

  2. INSPECT HYBRID WATER PUMP RELAY (A/C W/PMP)

    1. Check the signal reading of the hybrid water pump relay (A/C W/PMP relay).

      Click here

      OK

      A normal signal reading is output.

    Result

    Proceed to

    OK

    NG
    NG

    REPLACE HYBRID WATER PUMP RELAY

    Click here

    OK

  3. INSPECT HEATER ACCESSORY ASSEMBLY

    1. Remove the heater accessory assembly.

      Click here

    2. Inspect the heater accessory assembly.

      Click here

    Result

    Proceed to

    OK

    NG
    NG

    REPLACE HEATER ACCESSORY ASSEMBLY

    Click here

    OK

  4. CHECK HARNESS AND CONNECTOR (HYBRID WATER PUMP RELAY - BATTERY)

    1. E334424C01

      *1

      No. 2 Engine Room Relay Block

      *2

      Hybrid Water Pump Relay (A/C W/PMP Relay) Holder

      Remove the hybrid water pump relay (A/C W/PMP relay).

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

      Standard Voltage

      Tester Connection

      Switch Condition

      Specified Condition

      Relay terminal 1 - Body ground

      Power switch off

      11 to 14 V

      Relay terminal 5 - Body ground

      Power switch off

      11 to 14 V

    Result

    Proceed to

    OK

    NG
    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  5. CHECK HARNESS AND CONNECTOR (HEATER ACCESSORY ASSEMBLY - HYBRID WATER PUMP RELAY AND BODY GROUND)

    1. Disconnect the A106 heater accessory assembly connector.

    2. Remove the hybrid water pump relay (A/C W/PMP relay).

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

      Standard Resistance

      Tester Connection

      Condition

      Specified Condition

      A106-2 (+B) - Relay terminal 3

      Always

      Below 1 Ω

      A106-2 (+B) or Relay terminal 3 - Body ground

      Always

      10 kΩ or higher

      A106-1 (-) - Body ground

      Always

      Below 1 Ω

    Result

    Proceed to

    OK

    NG
    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  6. CHECK HARNESS AND CONNECTOR (HYBRID WATER PUMP RELAY - HYBRID VEHICLE CONTROL ECU)

    1. Remove the hybrid water pump relay (A/C W/PMP relay).

    2. Disconnect the A65 hybrid vehicle control ECU connector.

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

      Standard Resistance

      Tester Connection

      Condition

      Specified Condition

      Relay terminal 2 - A65-32 (WP)

      Always

      Below 1 Ω

      Relay terminal 2 or A65-32 (WP)- Body ground

      Always

      10 kΩ or higher

    Result

    Proceed to

    OK

    NG
    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  7. CHECK HYBRID VEHICLE CONTROL ECU

    1. E334425C02

      *1

      Component with harness connected

      (Hybrid Vehicle Control ECU)

      Remove the hybrid vehicle control ECU with the connectors still connected.

      Click here

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

      Standard Voltage

      Tester Connection

      Switch Condition

      Specified Condition

      A65-32 (WP) - Body ground

      • Power switch on (READY)

      • Air conditioning system not operated

      11 to 14 V

      A65-32 (WP) - Body ground

      • Power switch on (READY)

      • Air conditioning system operated

      Below 2 V

    Result

    Proceed to

    OK

    NG
    OK

    PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE

    Click here

    NG

    REPLACE HYBRID VEHICLE CONTROL ECU

    Click here