Toyota Tundra. Manual — part 2431

Fig. 143: Identifying Terminals Of J19 Air Conditioning Amplifier Connector
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

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

Standard Resistance

TESTER CONNECTION SPECIFIED CONDITION CHART

Standard Voltage

TESTER CONNECTION SPECIFIED CONDITION CHART

NG: REPAIR OR REPLACE HARNESS OR CONNECTOR

OK: PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS
TABLE (See PROBLEM SYMPTOMS TABLE )

IG POWER SOURCE CIRCUIT

DESCRIPTION

When the ignition switch is turned ON, positive (+) battery voltage is applied to the air conditioning amplifier.

WIRING DIAGRAM

Tester Connection

Condition Specified Condition

J19-14 (GND) -Body ground Always

Below 1 ohms

Tester Connection

Condition Specified Condition

J19-21 (B) - Body ground Always

11 to 14 V

2009 Toyota Tundra

2009 HVAC Air Conditioning - Tundra

Fig. 144: IG Power Source - Wiring Diagram
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

INSPECTION PROCEDURE

1. INSPECT FUSE (ECU-IG NO. 1)

a. Remove the ECU-IG No. 1 fuse from the main body ECU.

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

Standard Resistance

TESTER CONNECTION SPECIFIED CONDITION CHART

NG: REPLACE FUSE

OK: Go to Next Step

2. CHECK HARNESS AND CONNECTOR (AIR CONDITIONING AMPLIFIER - BATTERY AND

BODY GROUND)

a. Disconnect the J19 air conditioning amplifier connector.

Tester Connection Condition Specified Condition

ECU-IG No. 1 fuse Always

Below 1 ohms

2009 Toyota Tundra

2009 HVAC Air Conditioning - Tundra

Fig. 145: Identifying Terminals Of J19 Air Conditioning Amplifier Connector
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

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

Standard Resistance

TESTER CONNECTION SPECIFIED CONDITION CHART

Standard Voltage

TESTER CONNECTION SPECIFIED CONDITION CHART

NG: REPAIR OR REPLACE HARNESS OR CONNECTOR

OK: PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS
TABLE (See PROBLEM SYMPTOMS TABLE )

REFRIGERANT

ON-VEHICLE INSPECTION

1. INSPECT REFRIGERANT PRESSURE WITH MANIFOLD GAUGE SET

a. This method uses a manifold gauge set to locate problem areas. Read the manifold gauge pressure

when these conditions are established.

Test conditions:



Temperature at the air inlet is 30 to 35°C (86 to 95°F).

Tester Connection

Condition Specified Condition

J19-14 (GND) - Body ground Always

Below 1 ohms

Tester Connection

Switch Condition Specified Condition

J19-1 (IG+) - Body ground Ignition switch ON

11 to 14 V

2009 Toyota Tundra

2009 HVAC Air Conditioning - Tundra



Engine is running at 1500 RPM.



All doors are fully open.



Blower speed control switch is at HI.



Air inlet control set at "RECIRC"



A/C switch is ON.

Gauge readings (Reference)

Fig. 146: Refrigerant Pressure Graph
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

1. Normally functioning refrigeration system

Gauge reading

REFRIGERATION SYSTEM PRESSURE REFERENCE

Pressure side

Refrigerant volume

Low

0.15 to 0.25 MPa (1.5 to 2.5 kgf/cm

2

)

High

1.37 to 1.57 MPa (14 to 16 kgf/cm

2

)

2009 Toyota Tundra

2009 HVAC Air Conditioning - Tundra