Toyota Venza: Air Conditioning Control Panel Circuit

Toyota Venza Service Manual / Heating / Air Conditioning / Air Conditioning System / Air Conditioning Control Panel Circuit

DESCRIPTION

This circuit consists of the air conditioning control assembly and the A/C amplifier. When the air conditioning control assembly is operated, signals are transmitted to the A/C amplifier through the LIN communication system.

If the LIN communication system malfunctions, the A/C amplifier does not operate even if the air conditioning control assembly is operated.

WIRING DIAGRAM

CAUTION / NOTICE / HINT

NOTICE:

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

PROCEDURE

1.	CHECK HARNESS AND CONNECTOR (AIR CONDITIONING CONTROL ASSEMBLY - BODY GROUND)

(a) Disconnect the air conditioning control assembly connector.

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

Standard Resistance:

Tester Connection	Condition	Specified Condition
E3-5 (GND) - Body ground	Always	Below 1 Ω

Text in Illustration

*1	Front view of wire harness connector (to Air Conditioning Control Assembly)

REPAIR OR REPLACE HARNESS OR CONNECTOR

2.	CHECK HARNESS AND CONNECTOR (AIR CONDITIONING CONTROL ASSEMBLY - BATTERY)

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

Standard Voltage:

Tester Connection	Condition	Specified Condition
E3-4 (IG+) - E3-5 (GND)	Ignition switch ON	11 to 14 V

Text in Illustration

*1	Front view of wire harness connector (to Air Conditioning Control Assembly)

REPAIR OR REPLACE HARNESS OR CONNECTOR

3.	CHECK HARNESS AND CONNECTOR (A/C AMPLIFIER - AIR CONDITIONING CONTROL ASSEMBLY)

(a) Disconnect the A/C amplifier connector.

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

Standard Resistance:

Tester Connection	Condition	Specified Condition
D47-37 (LIN1) - E3-2 (LIN1)	Always	Below 1 Ω
D47-37 (LIN1) - Body ground	Always	10 kΩ or higher

Text in Illustration

Front view of wire harness connector

(to A/C Amplifier)

Front view of wire harness connector

(to Air Conditioning Control Assembly)

REPAIR OR REPLACE HARNESS OR CONNECTOR

4.	INSPECT AIR CONDITIONING CONTROL ASSEMBLY

(a) Replace the air conditioning control assembly (See page ).

HINT:

Since the air conditioning control assembly cannot be inspected while it is removed from the vehicle, replace the air conditioning control assembly with a new or a known good one and check that the condition returns to normal.

(b) Operate the air conditioning control assembly to check that it functions properly.

Result	Proceed to
Air conditioning control assembly malfunctions	A
Air Conditioning control assembly functions properly	B

PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE

REPLACE AIR CONDITIONING CONTROL ASSEMBLY

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