AIR CONDITIONING SYSTEM 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

CAUTION / NOTICE / HINT

PROCEDURE

1. CHECK CAN COMMUNICATION SYSTEM

   
   

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

      Click here

      OK
      CAN communication system DTCs are not output.

      Result
      Proceed to OK NG

   
   

   NG

   GO TO CAN COMMUNICATION SYSTEM Click here

   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. 

      *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 A54 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 A54-2 - Relay terminal 3 Always Below 1 Ω A54-2 or Relay terminal 3 - Body ground Always 10 kΩ or higher A54-1 - 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 A60 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 - A60-32 (WP) Always Below 1 Ω Relay terminal 2 or A60-32 (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

   

   *a

   Component with harness connected (Hybrid Vehicle Control ECU)

   -

   -

   
   

   1. 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 A60-32 (WP) - Body ground Power switch on (READY) A/C switch off 11 to 14 V A60-32 (WP) - Body ground Power switch on (READY) A/C switch on 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