Toyota 4Runner: IG Power Source Circuit

Toyota 4Runner Service Manual / Vehicle Interior / Heating / Air Conditioning / Air Conditioning System(for Manual Air Conditioning System) / 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
F42-1 (IG+) - Body ground	Ignition switch ON	11 to 14 V

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)

PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE

REPAIR OR REPLACE HARNESS OR CONNECTOR

Back-up Power Source Circuit

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Air Conditioning Unit

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