Toyota Tundra. Manual — part 2413

Fig. 87: Identifying Air Conditioning System (Manual) Parts Location (4 Of 4)
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

SYSTEM DIAGRAM

2009 Toyota Tundra

2009 HVAC Air Conditioning - Tundra

Fig. 88: Air Conditioning System (Manual) Diagram
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

Communication table

COMMUNICATION CHART

SYSTEM DESCRIPTION

1. GENERAL

Sender

Receiver

Signal

Line

Integration Control and Panel Air Conditioning Amplifier

A/C control signal

LIN

ECM

Air Conditioning Amplifier



Engine speed



Engine coolant temperature signal

CAN

2009 Toyota Tundra

2009 HVAC Air Conditioning - Tundra

a. The air conditioning system has the following controls:

SYSTEM REFERENCE CHART

2. MODE POSITION AND DAMPER OPERATION (for Regular Cab and Double Cab)

a. Mode Position and Damper Operation

Control

Outline

Manual
Control

The air conditioning amplifier controls the damper positions (air inlet control
damper, air mix control damper and mode control damper) and blower speed in
accordance with the positions of the switches (temperature control switch, blower
switch, mode select switch and air inlet control switch).

MAX A/C

Control

When the temperature control switch is in the MAX A/C position, the air
conditioning amplifier turns the compressor on and activates the servo motor (air
inlet) to set the air inlet control damper to the RECIRC position, improving the
cooling efficiency.

Compressor

Control

Through the calculation of the target evaporator temperature based on various
sensor signals, the air conditioning amplifier optimally controls the discharge
capacity by regulating the opening extent of the air conditioning compressor
solenoid valve.
The air conditioning amplifier compares the pulley speed signals, which are
transmitted by the lock sensor located on the air conditioning compressor, with the
engine speed signals, which are transmitted by the ECM (crankshaft position
sensor). When the air conditioning amplifier determines that the pulley is locked, it
turns off the magnetic clutch.

Self-

Diagnosis

A DTC (Diagnostic Trouble Code) is stored in the memory when the air
conditioning amplifier detects a problem with the air conditioning system.

2009 Toyota Tundra

2009 HVAC Air Conditioning - Tundra

Fig. 89: Mode Position And Damper Operation (For Regular Cab And Double Cab)
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

Functions of Main Dampers:

FUNCTIONS OF MAIN DAMPERS

Control

Damper

Operation Position

Damper

Position

Operation

Air Inlet

Control

Damper

FRESH

B

Brings in fresh air.

RECIRC

A

Recirculates internal air.

Air Mix

Control

Damper

MAX COLD to

MAX HOT

Temperature Setting

C - E
F - H

I - K

Varies the mixture ratio of fresh air and recirculated
air in order to regulate the temperature
continuously from HOT to COLD.

FACE

O, P, T, W

Air blows out of the front center register, side
registers, and footwell ducts.*1

2009 Toyota Tundra

2009 HVAC Air Conditioning - Tundra