Toyota Tacoma (2015-2018) Service Manual: Room Temperature Sensor Circuit (B1411/11)

Toyota Tacoma (2015-2018) Service Manual / Air Conditioning / Air Conditioning System(for Automatic Air Conditioning System) / Room Temperature Sensor Circuit (B1411/11)

DESCRIPTION

The cooler thermistor (room temperature sensor) is installed in the instrument panel to detect the cabin temperature which is used to control the air conditioning system AUTO mode. The resistance of the cooler thermistor (room temperature sensor) changes in accordance with the cabin temperature. As the temperature decreases, the resistance increases. As the temperature increases, the resistance decreases.

The air conditioning amplifier assembly applies a voltage (5 V) to the cooler thermistor (room temperature sensor) and reads voltage changes due to changes in the resistance of the cooler thermistor (room temperature sensor).

DTC No.	DTC Detection Condition	Trouble Area
B1411/11	Open or short in cooler thermistor (room temperature sensor) circuit	Cooler thermistor (room temperature sensor) Harness or connector Air conditioning amplifier assembly

WIRING DIAGRAM

PROCEDURE

1.	READ VALUE USING TECHSTREAM

(a) Connect the Techstream to the DLC3.

(b) Turn the ignition switch to 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 Temperature Sensor	Cooler thermistor (room temperature sensor) / min.: -6.50°C (20.30°F) max.: 57.25°C (135.05°F)	Actual cabin temperature displayed	-

Tester Display

Measurement Item/Range

Normal Condition

Diagnostic Note

Room Temperature Sensor

Cooler thermistor (room temperature sensor) /

min.: -6.50°C (20.30°F)

max.: 57.25°C (135.05°F)

Actual cabin temperature displayed

OK:

The display is as specified in the Normal Condition column.

Result	Proceed to
NG	A
OK (When troubleshooting according to Problem Symptoms Table)	B
OK (When troubleshooting according to the DTC)	C

PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE

REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY

2.	INSPECT COOLER THERMISTOR (ROOM TEMPERATURE SENSOR)

(a) Remove the cooler thermistor (room temperature sensor) (See page (b) Inspect the cooler thermistor (room temperature sensor) (See page ).

(b) Inspect the cooler thermistor (room temperature sensor) (See page ).

REPLACE COOLER THERMISTOR (ROOM TEMPERATURE SENSOR)

3.	CHECK HARNESS AND CONNECTOR (COOLER THERMISTOR (ROOM TEMPERATURE SENSOR) - AIR CONDITIONING AMPLIFIER ASSEMBLY)

(a) Disconnect the R36 cooler thermistor (room temperature sensor) connector.

(b) Disconnect the A36 air conditioning amplifier assembly connector.

Standard Resistance:

Tester Connection	Condition	Specified Condition
R36-1 - A36-16 (TR)	Always	Below 1 Ω
R36-2 - A36-26 (SG-1)	Always	Below 1 Ω
R36-1 or A36-16 (TR) - Body ground	Always	10 kΩ or higher
R36-2 or A36-26 (SG-1) - Body ground	Always	10 kΩ or higher

REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY

REPAIR OR REPLACE HARNESS OR CONNECTOR

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Other materials:

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Problem Symptoms Table
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Disassembly
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