2003 NISSAN TEANA sensor

ATC-78
TROUBLE DIAGNOSIS

Magnet Clutch CircuitBJS000G6
SYMPTOM: Magnet clutch does not engage.
INSPECTION FLOW
*1ATC-105, "Intake Sensor Circuit"*2ATC-96, "Ambient Sensor Circuit"*3AT C - 4 7 , "FUNCTION CONFIRMA-
TION PROCEDURE", see No. 13.
*4ATC-79, "
DIAGNOSIS PROCE-
DURE FOR MAGNET CLUTCH"
*5ATC-88, "TROUBLE DIAGNOSIS
FOR UNUSUAL PRESSURE"
*6AT C - 5 4 , "Operational Check"
*7ATC-47, "FUNCTION CONFIRMA-
TION PROCEDURE", see No. 2 to 6.*8ATC-35, "
SYMPTOM TABLE"
RJIA3270E

TROUBLE DIAGNOSIS
ATC-79
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SYSTEM DESCRIPTION
Unified meter and A/C amp. controls compressor operation by intake air temperature and signal from ECM.
Low Temperature Protection Control
Unified meter and A/C amp. will turn the compressor ON or OFF as determined by a signal detected by intake
sensor.
When intake air temperature is higher than 4°C (39°F), the compres-
sor turns ON. The compressor turns OFF when intake air tempera-
ture is lower than 2.5°C (37°F).
DIAGNOSIS PROCEDURE FOR MAGNET CLUTCH
SYMPTOM: Magnet clutch does not engage when A/C switch is ON.
1. CHECK INTAKE SENSOR CIRCUIT
Check intake sensor. Refer to AT C - 4 7 , "
FUNCTION CONFIRMATION PROCEDURE" , see No. 11.
OK or NG
OK >> GO TO 2.
NG >> Malfunctioning intake sensor: Refer to ATC-105, "
Intake Sensor Circuit" .
2. PERFORM AUTO ACTIVE TEST
Refer to PG-21, "
Auto Active Test" .
Does the magnet clutch operate?
YES >>
WITH CONSULT-II: GO TO 5.

WITHOUT CONSULT-II: GO TO 6.
NO >> Check 10 A fuse (No. 79, located in IPDM E/R). Refer to PG-25, "
IPDM E/R Terminal Arrange-
ment" , and GO TO 3.
RHA094GD
PJIA0011E

TROUBLE DIAGNOSIS
ATC-81
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7. CHECK VOLTAGE FOR UNIFIED METER AND A/C AMP. (COMPRESSOR ON SIGNAL)
1. Reconnect BCM connector and unified meter and A/C amp.
connector.
2. Turn ignition switch ON.
3. Check voltage between unified meter and A/C amp. harness
connector M45 terminal 42 and ground.
OK or NG
OK >> GO TO 8.
NG-1 >> If the voltage is approx. 5 V when A/C switch is ON: Replace unified meter and A/C amp.
NG-2 >> If the voltage is approx. 0 V when A/C switch is OFF: Replace BCM.
8. CHECK REFRIGERANT PRESSURE SENSOR
WITH CONSULT-II
1. Start the engine.
2. Check voltage of refrigerant pressure sensor. Refer to EC-90,
"CONSULT-II Reference Value in Data Monitor Mode" (QR
engine) or EC-434, "
CONSULT-II Reference Value in Data Mon-
itor Mode" (VQ engine).
WITHOUT CONSULT-II
1. Start the engine.
2. Check voltage between ECM harness connector F101 terminal
70 and ground.
OK or NG
OK >>
WITH CONSULT-II: GO TO 9.

WITHOUT CONSULT-II: GO TO 10.
NG >> Refer to EC-339, "
REFRIGERANT PRESSURE SENSOR" (QR engine) or EC-748, "REFRIGER-
ANT PRESSURE SENSOR" (VQ engine).
Te r m i n a l s
Condition Voltage (+)
(-) Unified meter
and A/C amp.
connectorTerminal
No.
M45 42 GroundA/C switch: ON
(Blower motor oper-
ates.)Approx. 0 V
OFF switch: ON (A/C
System: OFF)Approx. 5 V
RJIA2007E
Terminals
Condition Voltage (+)
(-)
ECM con-
nectorTerminal No.
F10169 (QR engine)
GroundA/C switch: ON
(Blower motor
operates.)Approx. 1.0 - 4.0 V
70 (VQ engine)
SJIA1723E

TROUBLE DIAGNOSIS
ATC-83
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12. CHECK CAN COMMUNICATION
Check CAN communication. Refer to BCS-14, "
CAN Communication Inspection Using CONSULT-II (Self-
Diagnosis)" .

BCM – ECM

ECM – IPDM E/R

ECM – Unified meter and A/C amp.
OK or NG
OK >> Replace ECM.
NG >> Repair or replace malfunctioning part(s).
COMPONENT INSPECTION
Refrigerant Pressure Sensor
The refrigerant pressure sensor is attached to the condenser.
Make sure that the A/C refrigerant pressure and the sensor output
voltage are as shown in the A/C operating condition figure. Refer to
EC-339, "
REFRIGERANT PRESSURE SENSOR" (QR engine) or
EC-748, "
REFRIGERANT PRESSURE SENSOR" (VQ engine).
RJIA1795E
RJIA2954E

TROUBLE DIAGNOSIS
ATC-89
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High-pressure Side is Too Low and Low-pressure Side is Too High
Both High- and Low-pressure Sides are Too Low
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 opera-
tion is improper.
↓
Damaged inside compressor
packings.Replace compressor.
No temperature difference
between high- and low-pres-
sure sides.Compressor pressure opera-
tion 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
difference between liquid
tank outlet and inlet. Outlet
temperature is extremely
low.

Liquid tank inlet and expan-
sion valve are frosted.Liquid tank inside is slightly
clogged.

Replace liquid tank.

Check lubricant for contami-
nation.

Temperature of expansion
valve inlet is extremely low
as compared with areas
near liquid tank.

Expansion valve inlet may
be frosted.

Temperature difference
occurs somewhere in high-
pressure side.High-pressure pipe located
between liquid tank and
expansion valve is clogged.

Check and repair malfunc-
tioning parts.

Check lubricant for contami-
nation.
Expansion valve and liquid
tank are warm or slightly cool
when touched.Low refrigerant charge.
↓
Leaking fittings or compo-
nents.Check refrigerant for leaks.
Refer to ATC-146, "
Checking
for 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 specifica-
tion.
↓
1. Improper expansion valve
adjustment
2. Malfunctioning expansion
valve.
3. Outlet and inlet may be
clogged.

Remove foreign particles by
using compressed air.

Replace expansion valve.

Check lubricant for contami-
nation.
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 lubricant for contami-
nation.
Air flow volume is not enough
or is too low.Evaporator is frozen.

Check intake sensor circuit.
Refer to ATC-105, "
Intake
Sensor Circuit" .

Replace compressor.

Repair evaporator fins.

Replace evaporator.

Refer to AT C - 7 2 , "Blower
Motor Circuit" .
AC353A

TROUBLE DIAGNOSIS
ATC-91
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Insufficient HeatingBJS000G8
SYMPTOM: Insufficient heating
INSPECTION FLOW
*1ATC-54, "Operational Check"*2ATC-66, "Air Mix Door Motor Circuit"*3AT C - 4 7 , "FUNCTION CONFIRMA-
TION PROCEDURE", see No. 2 to
6.
*4ATC-47, "
FUNCTION CONFIRMA-
TION PROCEDURE", see No. 13.*5ATC-59, "
LAN System Circuit"*6AT C - 7 2 , "Blower Motor Circuit"
*7EC-131, "DTC P0117, P0118 ECT
SENSOR" (QR engine) or EC-474,
"DTC P0117, P0118 ECT SEN-
SOR" (VQ engine)*8CO-10, "
Changing Engine Coolant"
(QR engine) or CO-34, "
Changing
Engine Coolant" (VQ engine)*9CO-14, "
Checking Radiator Cap"
(QR engine) or CO-38, "
Checking
Radiator Cap" (VQ engine)
RJIA3273E

ATC-96
TROUBLE DIAGNOSIS

Ambient Sensor CircuitBJS000GC
COMPONENT DESCRIPTION
Ambient Sensor
The ambient sensor is attached on the hood lock stay. It detects
ambient temperature and converts it into a resistance value which is
then input into the unified meter and A/C amp.
AMBIENT TEMPERATURE INPUT PROCESS
The unified meter and A/C amp. includes a processing circuit for the ambient sensor input. However, when the
temperature detected by the ambient sensor increases quickly, the processing circuit retards the unified meter
and A/C amp. function. It only allows the unified meter and A/C amp. to recognize an ambient temperature
increase of 0.33°C (0.6°F) per 100 seconds.
As an example, consider stopping for a few minutes after high speed driving. Although the actual ambient tem-
perature has not changed, the temperature detected by the ambient sensor will increase. This is because the
heat from the engine compartment can radiate to the front grille area, location of the ambient sensor.
DIAGNOSIS PROCEDURE FOR AMBIENT SENSOR
SYMPTOM: Ambient sensor circuit is open or shorted. (21 or − 21 is
indicated on unified meter and A/C amp. as a result of performing
self-diagnosis STEP-2.)
1. CHECK VOLTAGE BETWEEN AMBIENT SENSOR AND GROUND
1. Disconnect ambient sensor connector.
2. Turn ignition switch ON.
3. Check voltage between ambient sensor harness connector
E257 terminal 1 and ground.
OK or NG
OK >> GO TO 2.
NG >> GO TO 4.
RJIA2779E
RJIA1461E
1 – Ground : Approx. 5 V
RJIA2017E

TROUBLE DIAGNOSIS
ATC-97
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2. CHECK CIRCUIT CONTINUITY BETWEEN AMBIENT SENSOR AND UNIFIED METER AND A/C AMP.
1. Turn ignition switch OFF.
2. Disconnect unified meter and A/C amp. connector.
3. Check continuity between ambient sensor harness connector
E257 terminal 2 and unified meter and A/C amp. harness con-
nector M45 terminal 49.
OK or NG
OK >> GO TO 3.
NG >> Repair harness or connector.
3. CHECK AMBIENT SENSOR
Refer to AT C - 9 8 , "
Ambient Sensor" .
OK or NG
OK >> 1. Replace unified meter and A/C amp.
2. Go to self-diagnosis AT C - 4 7 , "
FUNCTION CONFIRMATION PROCEDURE" and perform self-
diagnosis STEP-2. Confirm that code No. 20 is displayed.
NG >> 1. Replace ambient sensor.
2. Go to self-diagnosis AT C - 4 7 , "
FUNCTION CONFIRMATION PROCEDURE" and perform self-
diagnosis STEP-2. Confirm that code No. 20 is displayed.
4. CHECK CIRCUIT CONTINUITY BETWEEN AMBIENT SENSOR AND UNIFIED METER AND A/C AMP.
1. Turn ignition switch OFF.
2. Disconnect unified meter and A/C amp. connector.
3. Check continuity between ambient sensor harness connector
E257 terminal 1 and unified meter and A/C amp. harness con-
nector M45 terminal 39.
4. Check continuity between ambient sensor harness connector
E257 terminal 1 and ground.
OK or NG
OK >> 1. Replace unified meter and A/C amp.
2. Go to self-diagnosis AT C - 4 7 , "
FUNCTION CONFIRMATION PROCEDURE" and perform self-
diagnosis STEP-2. Confirm that code No. 20 is displayed.
NG >> Repair harness or connector.2 – 49 : Continuity should exist.
RJIA2018E
1 – 39 : Continuity should exist.
1 – Ground : Continuity should not exist.
RJIA2019E