Last Modified: 04-05-2023 6.11:8.1.0 Doc ID: RM100000000VJF4
Model Year Start: 2016 Model: Sienna Prod Date Range: [12/2015 - 08/2016]
Title: NETWORKING: LIN COMMUNICATION SYSTEM: LIN Communication Circuit; 2016 MY Sienna [12/2015 - 08/2016]

LIN Communication Circuit

DESCRIPTION

When a switch of the air conditioning control assembly or air conditioning control assembly No. 2 are operated, the air conditioning control assembly or air conditioning control assembly No. 2 uses LIN communication to communicate with air conditioning amplifier assembly. If a switch of the air conditioning control assembly or air conditioning control assembly No. 2 does not operate properly, a problem with the LIN communication between the air conditioning control assembly or air conditioning control assembly No. 2 and air conditioning control amplifier may be causing the malfunction.

WIRING DIAGRAM

CAUTION / NOTICE / HINT

NOTICE:

  • When using the Techstream with the ignition switch off to troubleshoot:

    Connect the Techstream to the vehicle, and turn a courtesy switch on and off at 1.5 second intervals until communication between the Techstream and vehicle begins.

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

PROCEDURE

1.

CHECK HARNESS AND CONNECTOR (AIR CONDITIONING AMPLIFIER ASSEMBLY (A/C ECU) - EACH ECU)

Text in Illustration

*a

Front view of wire harness connector

(to Air Conditioning Amplifier Assembly (A/C ECU))

*b

Front view of wire harness connector

(to Air Conditioning Control Assembly)

*c

Front view of wire harness connector

(to No. 2 Air Conditioning Control Assembly)

-

-

(a) Disconnect the D75 and D74 air conditioning amplifier assembly (A/C ECU) connectors.

(b) Disconnect the D69 air conditioning control assembly connector.

(c) Disconnect the T7 No. 2 air conditioning control assembly connector.

(d) Measure the resistance and voltage according to the value(s) in the tables below.

Standard Resistance (Check for Open):

Tester Connection

Condition

Specified Condition

D75-37 (LIN1) - D69-8 (LIN1)

Always

Below 1 Ω

D74-13 (RLIN) - T7-2 (RLIN)

Always

Below 1 Ω

Standard Resistance (Check for Short):

Tester Connection

Condition

Specified Condition

D75-37 (LIN1) - Body ground

Always

10 kΩ or higher

D74-13 (RLIN) - Body ground

Always

10 kΩ or higher

Standard Voltage:

Tester Connection

Condition

Specified Condition

D75-37 (LIN1) - Body ground

Always

Below 1 V

D74-13 (RLIN) - Body ground

Always

Below 1 V

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

OK

2.

CHECK HARNESS AND CONNECTOR (AIR CONDITIONING CONTROL ASSEMBLY NO. 2 - BATTERY AND BODY GROUND)

(a) Disconnect the T7 No. 2 air conditioning control assembly connector.

(b) Measure the resistance and voltage according to the value(s) in the tables below.

Standard Resistance:

Tester Connection

Condition

Specified Condition

T7-4 (E) - Body ground

Always

Below 1 Ω

Standard Voltage:

Tester Connection

Switch Condition

Specified Condition

T7-1 (IG) - Body ground

Ignition switch ON

11 to 14 V

Text in Illustration

*a

Front view of wire harness connector

(to No. 2 Air Conditioning Control Assembly)

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

OK

3.

REPLACE NO. 2 AIR CONDITIONING CONTROL ASSEMBLY

(a) Temporarily replace the No. 2 air conditioning control assembly with a new or normally functioning one (See page 2016 - 2020 MY Sienna [12/2015 -        ]; HEATING / AIR CONDITIONING: REAR AIR CONDITIONING PANEL: REMOVAL ).

(b) Check that the No. 2 air conditioning control assembly function is normal.

OK:

No. 2 Air conditioning control assembly function is normal.

OK

END (AIR CONDITIONING CONTROL ASSEMBLY NO. 2 IS MALFUNCTIONING)

NG

4.

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

(a) Disconnect the D69 air conditioning control assembly connector.

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

D69-5 (GND) - Body ground

Always

Below 1 Ω

Standard Voltage:

Tester Connection

Switch Condition

Specified Condition

D69-4 (IG+) - Body ground

Ignition switch ON

11 to 14 V

Text in Illustration

*a

Front view of wire harness connector

(to Air Conditioning Control Assembly)

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

OK

5.

REPLACE AIR CONDITIONING CONTROL ASSEMBLY

(a) Temporarily replace the air conditioning control assembly with a new or normally functioning one (See page 2016 - 2020 MY Sienna [12/2015 -        ]; HEATING / AIR CONDITIONING: AIR CONDITIONING PANEL: REMOVAL ).

(b) Check that the front air conditioning control assembly function is normal.

OK:

Front air conditioning control assembly function is normal.

OK

END (AIR CONDITIONING CONTROL ASSEMBLY IS MALFUNCTIONING)

NG

REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY (A/C ECU)