Lexus NX: IG Power Source Circuit

DESCRIPTION

The main power source is supplied to the air conditioning amplifier assembly when the power switch is on (IG).

The power is used for operating the air conditioning amplifier assembly, servo motors, etc.

WIRING DIAGRAM

CAUTION / NOTICE / HINT

NOTICE:

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

PROCEDURE

1.

CHECK HARNESS AND CONNECTOR (AIR CONDITIONING AMPLIFIER ASSEMBLY - BATTERY AND BODY GROUND)

(a) Disconnect the air conditioning amplifier assembly connector.

*a

Rear view of wire harness connector

(to Air Conditioning Amplifier Assembly)

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

Standard Voltage:

Tester Connection

Switch Condition

Specified Condition

I50-1 (IG+) - Body ground

Power switch off

Below 1 V

I50-1 (IG+) - Body ground

Power switch on (IG)

11 to 14 V

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

I50-14 (GND) - Body ground

Always

Below 1 Ω

OK

PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

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