Last Modified: 04-05-2023 6.11:8.1.0 Doc ID: RM100000000ZXI7
Model Year Start: 2017 Model: Sienna Prod Date Range: [08/2016 -           ]
Title: HEATING / AIR CONDITIONING: AIR CONDITIONING SYSTEM: DIAGNOSIS SYSTEM; 2017 - 2020 MY Sienna [08/2016 -        ]

DIAGNOSIS SYSTEM

1. DESCRIPTION

(a) Air conditioning system data and the Diagnostic Trouble Codes (DTCs) can be read through the Data Link Connector 3 (DLC3) of the vehicle. When the system seems to be malfunctioning, use the Techstream to check for malfunctions and perform troubleshooting.

2. CHECK DLC3

(a) Check the DLC3 (See page 2016 - 2020 MY Sienna [12/2015 -        ]; INTRODUCTION: HOW TO TROUBLESHOOT ECU CONTROLLED SYSTEMS: GENERAL INFORMATION ).

3. LIST OF OPERATION METHODS

(a) By operating each of the air conditioning control switches as shown in the diagram below, it is possible to enter diagnostic check mode.

4. INDICATOR CHECK

(a) Turn the ignition switch off.

(b) Turn the ignition switch to ACC and wait at least 5 seconds.

(c) Turn the ignition switch to ON while pressing the A/C control AUTO switch and recirculation/fresh switch simultaneously. Hold both switches until the indicator check screen appears.

(d) The indicator check is automatically performed when panel diagnosis is activated. Check that the indicators light up and go off 4 times at 1 second intervals continuously.

*a

Indicator Blinking Pattern

*b

ON

*c

OFF

*d

1 second

HINT:

  • The sensor check automatically starts when the indicator check is completed.
  • Press the OFF switch to cancel the check mode.

5. SENSOR CHECK (DTC CHECK)

(a) Start the engine and warm it up.

(b) Perform the indicator check.

HINT:

After the indicator check is completed, the system enters DTC check mode automatically.

(c) Read the DTC displayed on the display.

*a

Diagnostic Trouble Code (DTC)

NOTICE:

In sensor check mode, which is automatically entered after indicator check mode, troubleshooting may be partially performed. Be sure to perform the actuator check, and then the sensor check again.

HINT:

Refer to Diagnostic Trouble Code Chart for details of the codes (See page 2017 - 2020 MY Sienna [08/2016 -        ]; HEATING / AIR CONDITIONING: AIR CONDITIONING SYSTEM: DIAGNOSTIC TROUBLE CODE CHART ).

  • When there are no problems, DTC 00 is output.
  • As an example, the illustration shows that display DTC 12 is output.

(d) If the steps are difficult to read because they change automatically, turn the driver side TEMP UP switch clockwise to display the steps one at a time so that they can be read easily. The items are displayed step by step each time the defroster switch is pressed.

HINT:

Press the OFF switch to finish panel diagnosis.

(e) Clear the DTC

(1) During the sensor check, press the defroster switch and rear defogger switch simultaneously.