RX400h · Service Manual HEATER & AIR CONDITIONING SYSTEM

IG Power Source Circuit

Circuit diagnosis

DESCRIPTION

This is the main power source supplied to the A/C amplifier assembly when the ignition switch is turned to the ON position. The power source is used for operating the A/C amplifier assembly and servomotor, etc.

WIRING DIAGRAM

E109245E03

INSPECTION PROCEDURE


1. INSPECT ECU-IG NO.1 FUSE
  1. Remove the ECU-IG No.1 fuse from the instrument panel J/B.

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

    Resistance:
    Tester item
    Condition
    Specified condition
    ECU-IG NO.1 fuse
    Always
    Below 1 Ω



NG
REPLACE ECU-IG NO.1 FUSE
OK


2. INSPECT AIR CONDITIONING AMPLIFIER ASSEMBLY

  1. E109265E29
    Remove the A/C amplifier assembly with the connectors still connected.

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

    Voltage:
    Tester connection
    (Symbols)
    Condition
    Specified condition
    A11-1 (IG+) - A11-6 (GND)
    Ignition switch ON
    10 to 14 V



NG
Go to step 3
OK

PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE

3. CHECK HARNESS AND CONNECTOR (A/C AMPLIFIER ASSEMBLY - BODY GROUND)

  1. E109218E21
    Disconnect the connector from the A/C amplifier assembly.

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

    Voltage:
    Tester connection
    (Symbols)
    Condition
    Specified condition
    A11-1 (IG+) - Body ground
    Ignition switch ON
    10 to 14 V



NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK


4. CHECK HARNESS AND CONNECTOR (A/C AMPLIFIER ASSEMBLY - BODY GROUND)

  1. E109218E22
    Measure the resistance according to the value(s) in the table below.

    Resistance:
    Tester connection
    (Symbols)
    Condition
    Specified condition
    A11-6 (GND) - Body ground
    Always
    Below 1 Ω



NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY


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