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Nissan Maxima. Manual - part 726

HAC-80

< SYMPTOM DIAGNOSIS >

[WITH COLOR DISPLAY]

INSUFFICIENT COOLING

SYMPTOM DIAGNOSIS

INSUFFICIENT COOLING

Component Function Check

INFOID:0000000010051014

Symptom

• Insufficient cooling

• No cool air comes out. (Airflow volume is normal.)

INSPECTION FLOW

CONFIRM SYMPTOM BY PERFORMING OPERATION CHECK - TEMPERATURE DECREASE

1. Press the AUTO switch.

2. Turn temperature control dial (driver side) counterclockwise until 18

°C (60°F) is displayed.

3. Check for cold air at discharge air outlets.
Is the inspection result normal?

YES

>> GO TO 3

>> GO TO 2

CHECK FOR ANY SYMPTOMS

Perform a complete operational check and check for any symptoms. Refer to

HAC-5, "Operational Check"

Does another symptom exist?

YES

>> Refer to

HA-21, "WITH COLOR DISPLAY : Symptom Matrix Chart"

>> System OK.

CHECK FOR SERVICE BULLETINS

Check for any service bulletins.

>> GO TO 4

CHECK DRIVE BELTS

Check compressor belt tension. Refer to

EM-14, "Checking Drive Belts"

Is the inspection result normal?

YES

>> GO TO 5

>> Adjust or replace A/C compressor belt. Refer to

EM-14, "Removal and Installation"

CHECK SETTING OF TEMPERATURE SETTING TRIMMER

Using CONSULT, check the setting of “TEMP SET CORRECT” on “WORK SUPPORT” of HVAC. Refer to

HAC-6, "Temperature Setting Trimmer"

1. Check that the temperature setting trimmer is set to “+ direction”.

NOTE:

The control temperature can be set with the setting of the temperature setting trimmer.

2. Set temperature control dial to “0”.
Is the symptom still present?

YES

>> GO TO 6.

>> Inspection End.

CHECK WITH SELF-DIAGNOSIS FUNCTION OF CONSULT

1. Using CONSULT, perform “SELF-DIAGNOSIS RESULTS” of HVAC.

2. Check if any DTC No. is displayed in the trouble diagnosis results.

NOTE:

If DTC is displayed along with DTC U1000 or U1010, first diagnose the DTC U1000 or U1010. Refer to

HAC-30, "DTC Logic"

HAC-31, "DTC Logic"

Is any DTC No. displayed?

YES

>> Perform diagnosis for the applicable DTC. Refer to

HAC-65, "DTC Index"

>> GO TO 7.

INSUFFICIENT COOLING

HAC-81

< SYMPTOM DIAGNOSIS >

[WITH COLOR DISPLAY]

HAC

CHECK WITH ACTIVE TEST OF CONSULT

1. Using CONSULT, perform “HVAC TEST”“ACTIVE TEST” of HVAC to check each output device. Refer to

HAC-26, "CONSULT Function"

NOTE:

Perform the ACTIVE TEST after starting the engine because the compressor is operating.

2. Refer to the table and check the outlet, inlet, airflow temperature, blower motor control signal, magnet

clutch operation, and air mix ratio. Visually check each operating condition, by listening for noise, touching

air outlets with a hand, etc.

Does it operate normally?

YES

>> GO TO 8.

NO-1 >> Air outlet does not change. Refer to

HAC-49, "Diagnosis Procedure"

NO-2 >> Air inlet does not change. Refer to

HAC-52, "Diagnosis Procedure"

NO-3 >> Discharge air temperature does not change. Refer to

HAC-45, "Diagnosis Procedure"

and

HAC-

47, "Diagnosis Procedure"

NO-4 >> Blower motor does not operate normally. Refer to

HAC-53, "Diagnosis Procedure"

NO-5 >> Magnet clutch does not operate. Refer to

HAC-57, "Diagnosis Procedure"

CHECK AIR MIX DOOR MOTOR OPERATION

Check and verify air mix door mechanism for smooth operation.
Does air mix door operate correctly?

YES

>> GO TO 9

>> Repair or replace air mix door control linkage.

CHECK COOLING FAN MOTOR OPERATION

Check and verify cooling fan motor for smooth operation.
Does cooling fan motor operate correctly?

YES

>> GO TO 10

>> Check cooling fan motor. Refer to

EC-486, "Component Function Check"

10.

CHECK RECOVERY/RECYCLING EQUIPMENT BEFORE USAGE

Check recovery/recycling equipment before connecting to vehicle. Verify there is no pressure in the recovery/

recycling equipment by checking the gauges. If pressure exists, recover refrigerant from equipment lines.

>> GO TO 11

11.

CHECK REFRIGERANT PURITY

1. Connect recovery/recycling equipment to vehicle.

2. Confirm refrigerant purity in supply tank using recovery/recycling and refrigerant indentifier.
Is the inspection result normal?

YES

>> GO TO 12

>> Check contaminated refrigerant. Refer to

HA-28, "Recycle Refrigerant"

and

HA-28, "Charge

Refrigerant"

12.

CHECK REFRIGERANT PRESSURE

Test item

MODE 1

MODE 2

MODE 3

MODE 4

MODE 5

MODE 6

Mode door position

VENT1

B/L1

B/L2

FOOT

D/F

DEF

Intake door position

REC

20%FRE

FRE

Air mix door position
(driver & passenger
side)

FULL COLD

FULL HOT

Blower motor duty ratio

37%

91%

65%

91%

Compressor (Magnet
clutch)

OFF

HAC-82

< SYMPTOM DIAGNOSIS >

[WITH COLOR DISPLAY]

INSUFFICIENT COOLING

Check refrigerant pressure with manifold gauge connected. Refer to

EC-515, "Component Function Check"

Is the inspection result normal?

YES

>> Perform diagnostic work flow. Refer to

HAC-82, "Diagnostic Work Flow"

>> GO TO 13

13.

CHECK FOR EVAPORATOR FREEZE-UP

Start engine and run A/C. Check for evaporator freeze-up.

NOTE:

Evaporator freeze up usually occurs at sustained highway speeds in hot, humid conditions with blend door at

full cold and blower on low speed, after 1-3 hours of continuous driving.
Does evaporator freeze up?

YES

>> Perform diagnostic work flow. Refer

HAC-82, "Diagnostic Work Flow"

>> GO TO 14

14.

CHECK AIR DUCTS

Check ducts for air leaks.
Is the inspection result normal?

YES

>> System OK.

>> Repair air leaks.

Diagnostic Work Flow

INFOID:0000000010051015

INSUFFICIENT COOLING

HAC-83

< SYMPTOM DIAGNOSIS >

[WITH COLOR DISPLAY]

HAC

HA-26, "Leak Test"

HA-37, "Removal and Installation for
Compressor"

HAC-84, "Performance Chart"

HA-19, "WITH COLOR DISPLAY :
Trouble Diagnoses for Abnormal
Pressure"

HAC-45, "Diagnosis Procedure"

(driver) or

HAC-47, "Diagnosis Pro-

cedure"

(passenger)

AWIIA0999GB

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