Nissan Tiida C11. Manual — part 910

HAC-304

< SYMPTOM DIAGNOSIS >

[AUTO AIR CONDITIONER (W/NAVI)]

INSUFFICIENT COOLING

Whenever system’s high and/or low side pressure(s) is/are unusual, diagnose using a manifold gauge. The
marker above the gauge scale in the following tables indicates the standard (usual) pressure range. Since the
standard (usual) pressure, however, differs from vehicle to vehicle, refer to above table (Ambient air tempera-
ture-to-operating pressure table).

Both High- and Low-pressure Sides are Too High

High-pressure Side is Too High and Low-pressure Side is Too Low

High-pressure Side is Too Low and Low-pressure Side is Too High

Gauge indication

Refrigerant cycle

Probable cause

Corrective action

Both high- and low-pressure
sides are too high.

Pressure is reduced soon af-
ter water is splashed on con-
denser.

Excessive refrigerant charge in refrig-
eration cycle.

Reduce refrigerant until
specified pressure is ob-
tained.

Air suction by cooling fan is in-
sufficient.

Insufficient condenser cooling perfor-
mance.

↓

Condenser fins are clogged.

Improper fan rotation of cooling
fan.

• Clean condenser.
• Check and repair cooling

fan if necessary.

• Low-pressure pipe is not

cold.

• When compressor is

stopped high-pressure val-
ue quickly drops by approx-
imately 196 kPa (1.96 bar, 2

kg/cm

, 28 psi). It then de-

creases gradually thereaf-
ter.

Poor heat exchange in condenser
(After compressor operation stops,
high-pressure decreases too slowly.).

↓

Air in refrigeration cycle.

Evacuate repeatedly and
recharge system.

Engine tends to overheat.

Engine cooling systems malfunction.

Check and repair each en-
gine cooling system.

• An area of the low-pressure

pipe is colder than areas
near the evaporator outlet.

• Plates are sometimes cov-

ered with frost.

• Excessive liquid refrigerant on low-

pressure side.

• Excessive refrigerant discharge

flow.

• Expansion valve is open a little

compared with the specification.

↓

Improper expansion valve adjust-
ment.

Replace expansion valve.

AC359A

Gauge indication

Refrigerant cycle

Probable cause

Corrective action

High-pressure side is too high
and low-pressure side is too low.

Upper side of condenser and
high-pressure side are hot,
however, liquid tank is not so
hot.

High-pressure tube or parts located
between compressor and condenser
are clogged or crushed.

• Check and repair or re-

place malfunctioning
parts.

• Check oil for contami-

nation.

AC360A

INSUFFICIENT COOLING

HAC-305

< SYMPTOM DIAGNOSIS >

[AUTO AIR CONDITIONER (W/NAVI)]

HAC

Both High- and Low-pressure Sides are Too Low

Low-pressure Side Sometimes Becomes Negative

Gauge indication

Refrigerant cycle

Probable cause

Corrective action

High-pressure side is too low
and low-pressure side is too
high.

High- and low-pressure sides
become equal soon after com-
pressor operation stops.

Compressor pressure operation
is improper.

↓

Damaged inside compressor
packings.

Replace compressor.

No temperature difference be-
tween high- and low-pressure
sides.

Compressor pressure operation
is improper.

↓

Damaged inside compressor
packings.

Replace compressor.

AC356A

Gauge indication

Refrigerant cycle

Probable cause

Corrective action

Both high- and low-pressure
sides are too low.

• There is a big temperature dif-

ference between liquid tank
outlet and inlet. Outlet tem-
perature is extremely low.

• Liquid tank inlet and expan-

sion valve are frosted.

Liquid tank inside is slightly
clogged.

• Replace liquid tank.
• Check oil for contamination.

• Temperature of expansion

valve inlet is extremely low as
compared with areas near liq-
uid tank.

• Expansion valve inlet may be

frosted.

• Temperature difference oc-

curs somewhere in high-pres-
sure side.

High-pressure pipe located be-
tween liquid tank and expansion
valve is clogged.

• Check and repair malfunc-

tioning parts.

• Check oil for contamination.

Expansion valve and liquid tank
are warm or only cool when
touched.

Low refrigerant charge.

↓

Leaking fittings or components

Check refrigerant for leaks.
Refer to

HA-22, "Checking of

Refrigerant Leaks"

There is a big temperature dif-
ference between expansion
valve inlet and outlet while the
valve itself is frosted.

Expansion valve closes a little
compared with the specification.

↓

Improper expansion valve
adjustment.

Malfunctioning expansion
valve.

Outlet and inlet may be
clogged.

• Remove foreign particles by

using compressed air.

• Replace expansion valve.
• Check oil for contamination.

An area of the low-pressure pipe
is colder than areas near the
evaporator outlet.

Low-pressure pipe is clogged or
crushed.

• Check and repair malfunc-

tioning parts.

• Check oil for contamination.

Air flow volume is not enough or
is too low.

Evaporator is frozen.

• Check intake sensor circuit.

Refer to

HAC-229, "Intake

Door Motor Component
Function Check"

• Replace compressor.
• Repair evaporator fins.
• Replace evaporator.
• Refer to

HAC-233, "Front

Blower Motor Component
Function Check"

AC353A

HAC-306

< SYMPTOM DIAGNOSIS >

[AUTO AIR CONDITIONER (W/NAVI)]

INSUFFICIENT COOLING

Low-pressure Side Becomes Negative

Gauge indication

Refrigerant cycle

Probable cause

Corrective action

Low-pressure side sometimes be-
comes negative.

• Air conditioning system does

not function and does not cy-
clically cool the compart-
ment air.

• The system constantly func-

tions for a certain period of
time after compressor is
stopped and restarted.

Refrigerant does not discharge
cyclically.

↓

Moisture is frozen at expan-
sion valve outlet and inlet.

↓

Water is mixed with refrigerant.

• Drain water from refrigerant

or replace refrigerant.

• Replace liquid tank.

AC354A

Gauge indication

Refrigerant cycle

Probable cause

Corrective action

Low-pressure side becomes nega-
tive.

Liquid tank or front/rear side of
expansion valve’s pipe is frost-
ed or dewed.

High-pressure side is closed
and refrigerant does not flow.

↓

Expansion valve or liquid tank
is frosted.

Leave the system at rest until
no frost is present. Start it
again to check whether or not
the malfunction is caused by
water or foreign particles.
• If water is the cause, initially

cooling is okay. Then the wa-
ter freezes causing a block-
age. Drain water from
refrigerant or replace refrig-
erant.

• If due to foreign particles, re-

move expansion valve and
remove the particles with dry
and compressed air (not
shop air).

• If either of the above meth-

ods cannot correct the mal-
function, replace expansion
valve.

• Replace liquid tank.
• Check oil for contamination.

AC362A