Toyota Venza: IG Power Source Circuit

Toyota Venza Service Manual / Heating / Air Conditioning / Air Conditioning System / IG Power Source Circuit

DESCRIPTION

The main power source is supplied to the A/C amplifier when the ignition switch is ON.

The power source is used for operating the A/C amplifier and servo motor, 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 IG1 relay or battery if the engine does not start.

PROCEDURE

1.	INSPECT A/C AMPLIFIER

(a) Remove the A/C amplifier with its connectors still connected.

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

Standard Voltage:

Tester Connection	Condition	Specified Condition
D47-1 (IG+) - D47-14 (GND)	Ignition switch off	Below 1 V
D47-1 (IG+) - D47-14 (GND)	Ignition switch ON	11 to 14 V

Text in Illustration

*1	Component with harness connected (A/C Amplifier)

PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE

2.	CHECK HARNESS AND CONNECTOR (A/C AMPLIFIER - BATTERY)

(a) Disconnect the A/C amplifier connector.

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

Standard Voltage:

Tester Connection	Condition	Specified Condition
D47-1 (IG+) - Body ground	Ignition switch off	Below 1 V
D47-1 (IG+) - Body ground	Ignition switch ON	11 to 14 V

Text in Illustration

*1	Front view of wire harness connector (to A/C Amplifier)

REPAIR OR REPLACE HARNESS OR CONNECTOR

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

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

Standard Resistance:

Tester Connection	Condition	Specified Condition
D47-14 (GND) - Body ground	Always	Below 1 Ω

Text in Illustration

*1	Front view of wire harness connector (to A/C Amplifier)

REPLACE A/C AMPLIFIER

REPAIR OR REPLACE HARNESS OR CONNECTOR

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