Toyota 4Runner manuals

Toyota 4Runner: IG Power Source Circuit

DESCRIPTION

The main power source is supplied to the air conditioning amplifier assembly when the ignition switch is turned to ON. The power source 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 inspection procedure.

HINT:

Start the engine before inspection. Check the relays, fuses and battery if the engine does not start.

PROCEDURE

1.

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

(a) Disconnect the F42 amplifier connector.


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

Standard Voltage:

Tester Connection

Switch Condition

Specified Condition

F42-1 (IG+) - Body ground

Ignition switch off

Below 1 V

Ignition switch ON

11 to 14 V

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

F42-14 (GND) - Body ground

Always

Below 1 Ω

Text in Illustration

*a

Rear view of wire harness connector

(to Air Conditioning Amplifier Assembly)


OK

PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE


NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

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