Air Conditioning System Back-Up Power Source Circuit

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

DESCRIPTION

WIRING DIAGRAM

INSPECTION PROCEDURE

INSPECT FUSE (A/C)

INSPECT AIR CONDITIONING AMPLIFIER (AIR CONDITIONING AMPLIFIER - BODY GROUND)

AIR CONDITIONING SYSTEM - Back-up Power Source Circuit


DESCRIPTION

The back-up power source circuit for the A/C amplifier is shown below. Power is supplied even when turning the engine switch off and is used for diagnostic trouble code memory, etc.

WIRING DIAGRAM


Lexus Is250, Is220D. Gse20 Ale20.Air Conditioning.Air Conditioning System.Air Conditioning System Back-Up Power Source Circuit


INSPECTION PROCEDURE

1.INSPECT FUSE (A/C)


    Lexus Is250, Is220D. Gse20 Ale20.Air Conditioning.Air Conditioning System.Air Conditioning System Back-Up Power Source Circuit

  1. Remove the A/C fuse from the cowl side junction block LH.

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

    Standard resistance:
    Tester Item
    		Condition
    		Specified Condition
    A/C fuse
    		Always
    		Below 1 Ω


NG
REPLACE FUSE (A/C)
OK


2.INSPECT AIR CONDITIONING AMPLIFIER (AIR CONDITIONING AMPLIFIER - BODY GROUND)


    Lexus Is250, Is220D. Gse20 Ale20.Air Conditioning.Air Conditioning System.Air Conditioning System Back-Up Power Source Circuit

  1. Disconnect the A/C amplifier connector.

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

    Standard voltage:
    Tester Connection
    		Condition
    		Specified Condition
    J58-1 (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