Toyota Venza: BUS IC Communication Malfunction (B1497/97)

Toyota Venza Service Manual / Heating / Air Conditioning / Air Conditioning System / BUS IC Communication Malfunction (B1497/97)

DESCRIPTION

The air conditioning harness connects the A/C amplifier and each servo. The A/C amplifier supplies power and sends operation instructions to each servo through the air conditioning harness. Each servo sends the damper position information to the A/C amplifier.

DTC No.	DTC Detection Condition	Trouble Area
B1497/97	Communication line error or open	Air conditioning harness A/C amplifier

WIRING DIAGRAM

PROCEDURE

1.	INSPECT A/C AMPLIFIER

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

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

Standard Resistance:

Tester Connection	Condition	Specified Condition
z7-2 (BUS G) - Body ground	Always	Below 1 Ω

Text in Illustration

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

REPLACE A/C AMPLIFIER

2.	INSPECT A/C AMPLIFIER

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

Standard Voltage:

Tester Connection	Condition	Specified Condition
z7-4 (B BUS) - z7-2 (BUS G)	Ignition switch off	Below 1 V
z7-4 (B BUS) - z7-2 (BUS G)	Ignition switch ON	11 to 14 V
z7-3 (BUS) - z7-2 (BUS G)	Ignition switch ON	Pulse generation

Text in Illustration

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

REPLACE AIR CONDITIONING HARNESS

REPLACE A/C AMPLIFIER

Compressor Solenoid Circuit (B1451/51)

DESCRIPTION In this circuit, the A/C compressor receives a refrigerant compression demand signal from the A/C amplifier. Based on this signal, the A/C compressor changes the amount of compressor o ...

Air Mix Damper Control Servo Motor Circuit (Driver Side) (B1446/46)

DESCRIPTION The air mix control servo motor sends pulse signals to indicate the damper position to the A/C amplifier. The A/C amplifier activates the motor (normal or reverse) based on these sign ...

Other materials about Toyota Venza:

Fail-safe Chart
FAIL-SAFE CHART 1. HID Headlight System (a) Light Control ECU (1) The light control ECU stops illuminating the HID headlights when any of the following abnormalities are detected. Condition Content Open in output si ...

Driver Side Power Mirror cannot be Adjusted with Power Mirror Switch
SYSTEM DESCRIPTION When the mirror adjust switch is operated, the main body ECU (driver side junction block assembly) detects the switch operation and sends the mirror adjust switch signal to the outer mirror control ECU assembly (driver door) via CAN com ...

Camshaft Position Sensor
Components COMPONENTS ILLUSTRATION Installation INSTALLATION PROCEDURE 1. INSTALL CAMSHAFT POSITION SENSOR (for Exhaust Side) (a) Apply a light coat of engine oil to the O-ring of the camshaft position sensor. NOTICE: If reusing the camshaft pos ...