Combustion Type Power Heater System Ecu Power Source Circuit

Heater & Air Conditioning System. Lexus Is250, Is220D. Gse20 Ale20
Heater. Lexus Is250, Is220D. Gse20 Ale20

DESCRIPTION

WIRING DIAGRAM

INSPECTION PROCEDURE

INSPECT FUSE (PWR HTR)

CHECK HARNESS AND CONNECTOR (POWER HEATER ECU (COMBUSTION HEATER ASSEMBLY) - BODY GROUND)

CHECK HARNESS AND CONNECTOR (POWER HEATER ECU (COMBUSTION HEATER ASSEMBLY) - BATTERY)

COMBUSTION TYPE POWER HEATER SYSTEM - ECU Power Source Circuit


DESCRIPTION

This is power source for the power heater ECU (combustion heater assembly).

WIRING DIAGRAM


Lexus Is250, Is220D. Gse20 Ale20.Heater.Combustion Type Power Heater System.Combustion Type Power Heater System Ecu Power Source Circuit


INSPECTION PROCEDURE

1.INSPECT FUSE (PWR HTR)


    Lexus Is250, Is220D. Gse20 Ale20.Heater.Combustion Type Power Heater System.Combustion Type Power Heater System Ecu Power Source Circuit

  1. Remove the PWR HTR fuse from the engine room R/B and J/B No. 1.

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

    Standard resistance:
    Inspection item
    		Condition
    		Specified condition
    PWR HTR fuse
    		Always
    		Below 1 Ω


NG
REPLACE FUSE (PWR HTR)
OK


2.CHECK HARNESS AND CONNECTOR (POWER HEATER ECU (COMBUSTION HEATER ASSEMBLY) - BODY GROUND)

  1. Remove the power heater ECU (combustion heater assembly).



    Lexus Is250, Is220D. Gse20 Ale20.Heater.Combustion Type Power Heater System.Combustion Type Power Heater System Ecu Power Source Circuit

  1. Disconnect the connector from the power heater ECU (combustion heater assembly).

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

    Standard resistance:
    Tester connection
    (Symbols)
    		Condition
    		Specified condition
    A51-1 (E) - Body ground
    		Always
    		Below 1 Ω


NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK


3.CHECK HARNESS AND CONNECTOR (POWER HEATER ECU (COMBUSTION HEATER ASSEMBLY) - BATTERY)


    Lexus Is250, Is220D. Gse20 Ale20.Heater.Combustion Type Power Heater System.Combustion Type Power Heater System Ecu Power Source Circuit

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

    Standard voltage:
    Tester connection
    (Symbols)
    		Condition
    		Specified condition
    A51-5 (B) - Body ground
    		Always
    		10 to 14 V


NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE