Last Modified: 04-05-2023 6.11:8.1.0 Doc ID: RM100000000ZPD4
Model Year Start: 2017 Model: Sienna Prod Date Range: [08/2016 -           ]
Title: HEATING / AIR CONDITIONING: AIR CONDITIONING SYSTEM: B1419/19; Rear Room Temperature Sensor Circuit; 2017 - 2020 MY Sienna [08/2016 -        ]

DTC

B1419/19

Rear Room Temperature Sensor Circuit

DESCRIPTION

This sensor detects the rear cabin temperature that is used as the basis for temperature control and sends a signal to the air conditioning amplifier.

DTC Code

DTC Detection Condition

Trouble Area

B1419/19

Rear room temperature sensor circuit (Open or short)

  • Rear room temperature sensor
  • Harness or connector between rear air conditioning room temperature sensor and air conditioning amplifier
  • Air conditioning amplifier

WIRING DIAGRAM

PROCEDURE

1.

READ VALUE USING AIR CONDITIONING AMPLIFIER ASSEMBLY

(a) Connect Techstream to the DLC3.

(b) Turn the ignition switch to ON.

(c) Turn the Techstream on.

(d) Enter the following menus: Body Electrical / Air Conditioner / Data List.

(e) Check the value(s) by referring to the table below.

Air Conditioner

Tester Display

Measurement Item/Range

Normal Condition

Diagnostic Note

Room Temp Sensor (Rear)

Rear room temperature sensor /

Min.: -6.5°C (20.3°F)

Max.: 57.25°C (135.05°F)

Actual cabin temperature is displayed

Open in the circuit: -6.5°C (20.3°F)

Short in the circuit: 57.25°C (135.05°F)

OK:

The display is as specified in the normal condition column.

Result

Result

Proceed to

NG

A

OK (When troubleshooting according to the PROBLEM SYMPTOMS TABLE)

B

OK (When troubleshooting according to the DTC)

C

B

PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE

C

REPLACE AIR CONDITIONING AMPLIFIER

A

2.

INSPECT REAR ROOM TEMPERATURE SENSOR

(a) Remove the rear room temperature sensor.

*a

Component without harness connected

(to Rear Room Temperature Sensor)

-

-

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

K11-1 - K11-2

10°C (50°F)

3.00 to 3.73 kΩ

15°C (59°F)

2.45 to 2.88 kΩ

20°C (68°F)

1.95 to 2.30 kΩ

25°C (77°F)

1.60 to 1.80 kΩ

30°C (86°F)

1.28 to 1.47 kΩ

35°C (95°F)

1.00 to 1.22 kΩ

40°C (104°F)

0.80 to 1.00 kΩ

45°C (113°F)

0.65 to 0.85 kΩ

50°C (122°F)

0.50 to 0.70 kΩ

55°C (131°F)

0.44 to 0.60 kΩ

60°C (140°F)

0.36 to 0.50 kΩ

NOTICE:

  • Hold the sensor only by its connector. Touching the sensor may change the resistance value.
  • When measuring, the sensor temperature must be the same as the rear cabin temperature.

HINT:

As the temperature increases, the resistance decreases (see the graph).

NG

REPLACE REAR ROOM TEMPERATURE SENSOR

OK

3.

CHECK HARNESS AND CONNECTOR (REAR ROOM TEMPERATURE SENSOR - AIR CONDITIONING AMPLIFIER)

(a) Disconnect the D186 air conditioning amplifier connector.

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

D186-20 (TR) - K11-1

Always

Below 1 Ω

D186-8 (RGND) - K11-2

Always

Below 1 Ω

D186-20 (TR) - Body ground

Always

10 kΩ or higher

D186-8 (RGND) - Body ground

Always

10 kΩ or higher

OK

REPLACE AIR CONDITIONING AMPLIFIER

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR