Nissan Maxima. Manual — part 713

HAC-28

< SYSTEM DESCRIPTION >

[WITH COLOR DISPLAY]

DIAGNOSIS SYSTEM (HVAC)

ACTIVE TEST

HVAC TEST

NOTE:
Perform the inspection of each output device after starting the engine because the compressor is operating.

WORK SUPPORT

NOTE:

ENG COOL TEMP

[

°C] Water temperature signal value received from ECM via CAN communication

VEHICLE SPEED

[mph

(km/h)]

Vehicle speed signal value received from meter via CAN communication

Monitor item [Unit]

Description

Test item

Description

HVAC TEST

The operation check of A/C system can be performed by selecting the mode. Refer to the fol-
lowing table for the conditions of each mode.

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

REC

20%FRE

FRE

FRE

FRE

Air mix door position
(driver & passenger
side)

FULL COLD

FULL COLD

FULL HOT

FULL HOT

FULL HOT

FULL HOT

Blower motor duty ratio

37%

91%

65%

65%

65%

91%

Compressor (Magnet
clutch)

ON

ON

OFF

OFF

ON

ON

Work item

Description

Reference

TEMP SET CORRECT
(Setting of difference between tem-
perature setting and control tempera-
ture)

If the temperature felt by the customer is different than the airflow
temperature controlled by the temperature setting, the auto ampli-
fier control temperature can be adjusted to compensate for the
temperature setting.

HAC-6, "Temperature
Setting Trimmer"

BLOW SET
(Blow setting to DEF in FOOT mode)

In the FOOT mode, the air blowing to the DEF can change ON/
OFF.

HAC-7, "Foot Position
Setting Trimmer"

FRE MEMORY SET
(FRE memory function setting)

• If the ignition switch is turned to the OFF position while the FRE

switch is set to ON (fresh air intake), “Perform the memory” or
“Do not perform the memory” of the FRE switch ON (fresh air in-
take) condition can be selected.

• If “Perform the memory” was set, the FRE switch will be ON

(fresh air intake) when turning the ignition switch to the ON posi-
tion again.

• If “Do not perform the memory” was set, the air inlets will be con-

trolled automatically when turning the ignition switch to the ON
position again.

HAC-7, "Inlet Port Mem-
ory Function (FRE)"

REC MEMORY SET
(REC memory function setting)

• If the ignition switch is turned to the OFF position while the REC

switch is set to ON (recirculation), “Perform the memory” or “Do
not perform the memory” of the REC switch ON (recirculation)
condition can be selected.

• If “Perform the memory” was set, the REC switch will be ON (re-

circulation) when turning the ignition switch to the ON position
again.

• If “Do not perform the memory” was set, the air inlets will be con-

trolled automatically when turning the ignition switch to the ON
position again.

HAC-8, "Inlet Port Mem-
ory Function (REC)"

DIAGNOSIS SYSTEM (HVAC)

HAC-29

< SYSTEM DESCRIPTION >

[WITH COLOR DISPLAY]

C

D

E

F

G

H

J

K

L

M

A

B

HAC

N

O

P

When the battery cable is disconnected from the negative terminal or when the battery voltage becomes 10V or less, the setting of
WORK SUPPORT may be cancelled.

HAC-30

< DTC/CIRCUIT DIAGNOSIS >

[WITH COLOR DISPLAY]

U1000 CAN COMM CIRCUIT

DTC/CIRCUIT DIAGNOSIS

U1000 CAN COMM CIRCUIT

Description

INFOID:0000000010050964

CAN (Controller Area Network) is a serial communication line for real time application. It is an on-vehicle mul-

tiplex communication line with high data communication speed and excellent error detection ability. Many elec-

tronic control units are equipped onto a vehicle, and each control unit shares information and links with other

control units during operation (not independent). In CAN communication, control units are connected with two

communication lines (CAN-H line, CAN-L line) allowing a high rate of information transmission with less wiring.

Each control unit transmits/receives data but selectively reads required data only.

CAN Communication Signal Chart. Refer to

LAN-14, "How to Use CAN Communication Signal Chart"

.

DTC Logic

INFOID:0000000010050965

DTC DETECTION LOGIC

Diagnosis Procedure

INFOID:0000000010050966

1.

CHECK WITH SELF-DIAGNOSIS FUNCTION OF CONSULT

1. Turn ignition switch ON and wait for 2 or more seconds.

2. Using CONSULT, perform “SELF-DIAGNOSIS RESULTS” of HVAC.
Is “CAN COMM CIRCUIT” displayed?

YES

>> Perform trouble diagnosis for the CAN communication system. Refer to

LAN-15, "Trouble Diagno-

sis Flow Chart"

.

NO

>> Perform the intermittent malfunction diagnosis. Refer to

GI-41, "Intermittent Incident"

.

DTC

Items

(CONSULT screen terms)

Diagnostic item is detected when...

Possible cause

U1000

CAN COMM CIRCUIT

When A/C auto amp. is not transmitting
or receiving CAN communication signal
for 2 or more seconds.

CAN communication system

U1010 CONTROL UNIT (CAN)

HAC-31

< DTC/CIRCUIT DIAGNOSIS >

[WITH COLOR DISPLAY]

C

D

E

F

G

H

J

K

L

M

A

B

HAC

N

O

P

U1010 CONTROL UNIT (CAN)

Description

INFOID:0000000010050967

Initial diagnosis of A/C auto amp.

DTC Logic

INFOID:0000000010050968

DTC DETECTION LOGIC

Diagnosis Procedure

INFOID:0000000010050969

1.

CHECK WITH SELF-DIAGNOSIS FUNCTION OF CONSULT

Using CONSULT, perform “SELF-DIAGNOSIS RESULTS” of HVAC.
Is DTC No.“U1010” displayed?

YES

>> Replace A/C auto amp. Refer to

HAC-100, "Removal and Installation"

.

NO

>> Inspection End.

DTC

Items

(CONSULT screen terms)

Diagnostic item is detected when...

Possible cause

U1010

CONTROL UNIT (CAN)

When detecting error during the initial diag-
nosis of CAN controller of A/C auto amp.

A/C auto amp.