Infiniti I35 (A33). Manual — part 534

RHA042I

7. Check ECON (Economy) Mode

NHHA0178S0207

1.

Set the temperature 75°F or 25°C.

2.

Press ECON switch.

3.

Display should indicate ECON (no AUTO).
Confirm that the compressor clutch is not engaged (sound or
visual inspection).
(Discharge air and blower speed will depend on ambient, in-
vehicle and set temperatures.)

If NG, go to trouble diagnosis procedure for ECON (Economy)
mode (HA-93).
If OK, continue with next check.

RHA043I

8. Check AUTO Mode

NHHA0178S0208

1.

Press AUTO switch.

2.

Display should indicate AUTO (no ECON).
Confirm that the compressor clutch engages (sound or visual
inspection).
(Discharge air and blower speed will depend on ambient, in-
vehicle and set temperatures.)

If NG, go to trouble diagnosis procedure for A/C system (HA-50),
then if necessary, trouble diagnosis procedure for magnet clutch
(HA-75).
If OK, continue with next check.

GI

MA

EM

LC

EC

FE

AT

AX

SU

BR

ST

RS

BT

SC

EL

IDX

TROUBLE DIAGNOSES

Operational Check (Cont’d)

HA-49

A/C System

TROUBLE DIAGNOSIS PROCEDURE FOR A/C SYSTEM

=NHHA0179

SYMPTOM:

I

A/C system does not come on.

INSPECTION FLOW

SHA607FA

*1: HA-51

*2: HA-47

*3: HA-51

RHA036IA

COMPONENT DESCRIPTION

NHHA0247

Automatic Amplifier (Auto Amp.)

NHHA0247S01

The auto amplifier has a built-in microcomputer which processes
information sent from various sensors needed for air conditioner
operation. The air mix door motor, mode door motor, intake door
motor, blower motor and compressor are then controlled.
The auto amplifier is unitized with control mechanisms. Signals
from various switches and Potentio Temperature Control (PTC) are
directly entered into auto amplifier.
Self-diagnostic functions are also built into auto amplifier to provide
quick check of malfunctions in the auto air conditioner system.

Potentio Temperature Control (PTC)

NHHA0247S02

The PTC is built into the A/C auto amp. It can be set at an interval
of 0.5°C (1.0°F) in the 18°C (60°F) to 32°C (90°F) temperature
range by pushing the temperature button. The set temperature is
digitally displayed.

TROUBLE DIAGNOSES

A/C System

HA-50

MAIN POWER SUPPLY AND GROUND CIRCUIT CHECK

=NHHA0180

Power Supply Circuit Check

NHHA0180S03

Check power supply circuit for air conditioner system.
Refer to EL-12, “Wiring Diagram — POWER —”.

SHA732F

DIAGNOSTIC PROCEDURE

NHHA0181

SYMPTOM:

I

A/C system does not come on.

1

CHECK POWER SUPPLY CIRCUIT FOR AUTO AMP.

Measure voltage across harness connector M60 terminal Nos. 26, 27, 33 and ground.

SHA319FE

OK or NG

OK

©

GO TO 2.

NG

©

Check auto amp. ground circuit.

I

Check 10A fuse [Nos. 12 and 28, located in the fuse block (J/B) and 15A fuses Nos.
51 and 52, located in the fuse and fusible link box].

I

If fuses are OK, check for open circuit in wiring harness. Repair or replace as neces-
sary.

I

If fuses are NG, replace fuse and check wiring harness for short circuit. Repair or
replace as necessary.

GI

MA

EM

LC

EC

FE

AT

AX

SU

BR

ST

RS

BT

SC

EL

IDX

TROUBLE DIAGNOSES

A/C System (Cont’d)

HA-51

2

CHECK BODY GROUND CIRCUIT FOR AUTO AMP.

Does continuity exist between auto amp. Harness connectors M60, M59 terminal Nos. 32, 14 and ground?

SHA320FA

Yes or No

Yes

©

Replace auto amp.
INSPECTION END

No

©

Repair or replace harness.

TROUBLE DIAGNOSES

A/C System (Cont’d)

HA-52