CHECK COMPARTMENT TEMPERATURE.
1) Turn the A/C switch to ON.
2) Turn the temperature control dial at maxi-
mum cool position.
3) Check the compartment temperature
change.

Does the compartment temper-
ature change?

Go to step

<Ref. to AC-18,
PROCEDURE,
Refrigerant Pres-
sure with Manifold
Gauge Set.>

CHECK A/C SYSTEM RESPONSE.
Change the temperature setting, and check the
response of A/C system.

Does the A/C system respond
quickly?

A/C system is nor-
mal.

<Ref. to AC(diag)-
19, COMPART-
MENT TEMPERA-
TURE DOES NOT
CHANGE, OR A/C
SYSTEM DOES
NOT RESPOND
PROMPTLY, Diag-
nostics for A/C
System Malfunc-
tion.>

AC(diag)-3

General Description

HVAC SYSTEM (AUTO A/C) (DIAGNOSTICS)

2. General Description

A: CAUTION

1) Never connect the battery in reverse polarity.

• Doing so may immediately damage the auto A/C

control module.

2) Do not disconnect the battery terminals while the

engine is running.

• A large counter electromotive force will be gener-

ated in the generator, and this voltage may damage

electronic parts such as auto A/C control module

etc.

3) Before disconnecting the connectors of sensors

and the auto A/C control module, be sure to turn off

the ignition switch.

• Auto A/C control module may be damaged.

4) Every A/C-related part is a precision part. Do not

drop them.

5) Airbag system wiring harness is routed near the

auto A/C control module and junction box.
CAUTION:

• Do not use electrical test equipment on the

airbag system wiring harness and connector.

• Be careful not to damage the airbag system

wiring harness when servicing the auto A/C

control module and junction box.

B: INSPECTION

Before performing the diagnosis, check the follow-

ing items which may cause problems in the A/C

system.

1. BATTERY

1) Measure the battery voltage and specific gravity

of the electrolyte.
Standard voltage:

12 V

Specific gravity:

1.260 or more

2) Check the condition of the fuses for A/C system

power supply and other fuses.

3) Check the condition of harness and harness

connector connections.

2. ASPIRATOR HOSE

1) Turn the ignition switch to ON, and press the A/C

switch.

2) Turn the temperature control dial to maximum

hot position.

3) Set the blow vents to the DEF position.

4) Turn the fan switch to “MAX” position.

5) Put a strip of paper close to the front side of in-

vehicle sensor suction port (A) located in the instru-

ment panel lower cover, and check that air is being

sucked into the port by seeing the paper moving to-

wards the port.
NOTE:

Be careful not to let the paper get sucked into the

port.

6) If the paper does not move at all, remove the in-

strument panel lower cover <Ref. to EI-49, RE-

MOVAL, Instrument Panel Lower Cover.> and

check for poor connection of the aspirator hose (A),

in-vehicle sensor and heater unit, and repair them if

necessary.

3. A/C LINE

Check the connection for A/C line (A) and lower

side high-pressure pipe.

4. CONTROL LINKAGE

1) Check the state of mode door linkage.

2) Check the state of air mix door linkage.

3) Check the state of intake door linkage.

AC-01714

(A)

AC-02460

(A)

AC-01878

(A)

AC(diag)-4

General Description

HVAC SYSTEM (AUTO A/C) (DIAGNOSTICS)

5. CONTROL SWITCHES

Start the engine and warm up completely.

1) Inspection using switches

2) Inspection of compressor operation

3) Inspection of illumination control

No.

Point to check

Switch operation

Judgment standard

Air flow control dial

Turn the dial to the right.

Outlet opening (mode) switches AUTO →
VENT → BI-LEVEL → HEAT → DEF/HEAT →
DEF each time turning the dial.

Fan speed control dial Turn the dial to the right.

Each time the dial is turned, the fan speed
switches OFF → AUTO → 1st → 2nd → 3rd →
4th → 5th → 6th → 7th.

FRESH/RECIRC
switch

Press the FRESH/RECIRC switch.

Inlet opening switches RECIRC → FRESH →
RECIRC each time pressing the switch. (LED
illuminates at RECIRC)

Set the air flow control dial and fan speed control

dial to the AUTO position.

The system switches to AUTO.

A/C switch

Turn the A/C switch to ON with the fan speed con-
trol dial set to other than OFF position.

The LED lights and the compressor operates.

Set the air flow control dial and fan speed control

dial to the AUTO position.

The system switches to AUTO.

Auto function
Operate in order from
1).

1) Set the following dial to AUTO.
• Air flow control dial
• Fan speed control dial
2) Turn the temperature control dial completely to
the left, and set to the maximum cool position.

• Outlet air temperature: COOL
• Fan speed: Max.
• Outlet opening: VENT
• Inlet opening: RECIRC
• Compressor: AUTO

3) Turn the temperature control dial to the right

slowly up to the maximum hot position.

• Outlet air temperature: COOL → HOT
• Fan speed: AUTO
• Outlet opening: AUTO
• Inlet opening: AUTO
• Compressor: AUTO

4) Turn the temperature control dial fully to the

right, to the maximum hot position.

• Outlet air temperature: HOT
• Fan speed: Max.
• Outlet opening: HEAT
• Inlet opening: FRESH
• Compressor: AUTO

Defroster Interlock
Function

Set the air flow control dial to the DEF or the DEF/
HEAT position.

• Outlet air temperature: AUTO
• Fan speed: AUTO
• Outlet opening: DEF or DEF/HEAT
• Inlet opening: FRESH
• Compressor: ON

Rear defogger switch

Press the rear defogger switch.

LED illuminates.

No.

Point to check

Switch operation

Judgment standard

Compressor

1) Turn the A/C switch to ON.
2) Set the FAN switch between LO and HI.

Compressor: ON

No.

Point to check

Switch operation

Judgment standard

Illumination

Turn the lighting switch to ON.

Illumination comes on.
If the LED lights, the LED will dim.

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