2005 INFINITI FX35 ignition

TROUBLE DIAGNOSIS ATC-87
C
D E
F
G H
I
K L
M A
B
AT C
Revision: 2005 July 2005 FX
5. CHECK BCM INPUT (COMPRESSOR ON) SIGNAL
Check compressor ON/OFF signal. Refer to AT C - 4 0 , "
CONSULT-II
Function (BCM)" .
OK or NG
OK >> GO TO 8.
NG >> GO TO 6.
6. CHECK CIRCUIT CONTINUITY BETWEEN BCM AND UNIFIED METER AND A/C AMP.
1. Turn ignition switch OFF.
2. Disconnect BCM connector and unified meter and A/C amp. connector.
3. Check continuity between BCM harness connector M3 terminal 27 (R/Y) and unified meter and A/C amp. harness connector
M57 terminal 42 (R/Y).
OK or NG
OK >> GO TO 7.
NG >> Repair harness or connector.
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 M57 terminal 42 (R/Y) 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. A/C SW ON : AIR COND SW ON
A/C SW OFF : AIR COND SW OFF
R J I A 1111 E
27 – 42 : Continuity should exist.
RJIA2006E
Te r m i n a l s
Condition Voltage
(+)
( − )
Unified meter
and A/C amp.
connector Terminal
No.
(wire color)
M57 42 (R/Y) Ground A/C switch: ON
(Blower motor operates.) Approx. 0 V
OFF switch: ON
(A/C system: OFF) Approx. 5 V
RJIA2007E

ATC-88
TROUBLE DIAGNOSIS
Revision: 2005 July 2005 FX
8. CHECK REFRIGERANT PRESSURE SENSOR
WITH CONSULT-II
1. Start the engine.
2. Check voltage of refrigerant pressure sensor. Refer to EC-147, "
CONSULT-II Reference Value in Data
Monitor" (VQ35DE) or EC-838, "CONSULT-II Reference Value in Data Monitor" (VK45DE).
WITHOUT CONSULT-II
1. Start the engine.
2. Check voltage between ECM harness connector F101 terminal 70 (L/R) and ground.
OK or NG
OK >>
WITH CONSULT-II
GO TO 9.

WITHOUT CONSULT-II
GO TO 10.
NG >> Refer to EC-674, "
REFRIGERANT PRESSURE SENSOR" (VQ35DE) or EC-1364, "REFRIGER-
ANT PRESSURE SENSOR" (VK45DE).
9. CHECK BCM INPUT (FAN ON) SIGNAL
Check FAN ON/OFF signal. Refer to AT C - 4 0 , "
CONSULT-II Function
(BCM)" .
OK or NG
OK >> GO TO 12.
NG >> GO TO 10.
10. CHECK CIRCUIT CONTINUITY BETWEEN BCM AND UNIFIED METER AND A/C AMP.
1. Turn ignition switch OFF.
2. Disconnect BCM connector and unified meter and A/C amp. connector.
3. Check continuity between BCM harness connector M3 terminal 28 (BR/Y) and unified meter and A/C amp. harness connector
M57 terminal 57 (BR/Y).
OK or NG
OK >> GO TO 11.
NG >> Repair harness or connector.
Te r m i n a l s
Condition Voltage
(+)
( − )
ECM
connector Terminal No.
(wire color)
F101 70 (L/R) Ground A/C switch: ON
(Blower motor operates.) Approx. 1 - 4 V
PBIB1188E
FAN SW ON : FAN ON SIG ON
FAN SW OFF : FAN ON SIG OFF
R J I A 1111 E
28 – 57 : Continuity should exist.
RJIA2009E

TROUBLE DIAGNOSIS ATC-89
C
D E
F
G H
I
K L
M A
B
AT C
Revision: 2005 July 2005 FX
11 . CHECK VOLTAGE FOR UNIFIED METER AND A/C AMP. (FAN 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 M57 terminal 57 (BR/Y) and ground.
OK or NG
OK >> GO TO 12.
NG-1 >> If the voltage is approx. 5 V when blower motor is ON: Replace unified meter and A/C amp.
NG-2 >> If the voltage is approx. 0 V when blower motor is OFF: Replace BCM. Refer to BCS-16,
"Removal and Installation of BCM" .
12. CHECK CAN COMMUNICATION
Check CAN communication. Refer to BCS-15, "
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 >> INSPECTION END
NG >> Repair or replace malfunctioning part(s).
Te r m i n a l s
Condition Voltage
(+)
(-)
Unified meter
and A/C amp. connector Terminal No.
(wire color)
M57 57 (BR/Y) Ground A/C switch: ON
(Blower motor operates.) Approx. 0 V
OFF switch: ON
(A/C system: OFF) Approx. 5 V
RJIA2010E

ATC-98
TROUBLE DIAGNOSIS
Revision: 2005 July 2005 FX
Low-pressure Side Sometimes Becomes Negative
Low-pressure Side Becomes Negative
DIAGNOSIS PROCEDURE FOR INSUFFICIENT COOLING
SYMPTOM: Insufficient cooling
1. CHECK POWER SUPPLY FOR ECV (ELECTRONIC CONTROL VALVE)
1. Disconnect compressor (ECV) connector.
2. Turn ignition switch ON.
3. Check voltage between compressor (ECV) harness connector F6 terminal 2 (G) and ground.
OK or NG
OK >> GO TO 2.
NG >> Check power supply circuit and 10 A fuse [No. 12, located in the fuse block (J/B)]. Refer to PG-82, "
FUSE
BLOCK - JUNCTION BOX (J/B)" .

If fuse is OK, check harness for open circuit. Repair or replace if necessary.

If fuse is NG, replace fuse and check harness for short circuit. Repair or replace if necessary.
Gauge indication Refrigerant cycle Probable cause Corrective action
Low-pressure side sometimes
becomes negative.

Air conditioning system
does not function and does
not cyclically cool the com-
partment air.

The system constantly func-
tions for a certain period of
time after compressor is
stopped and restarted. Refrigerant does not dis-
charge cyclically.
↓
Moisture is frozen at expan-
sion valve outlet and inlet.
↓
Water is mixed with refriger-
ant.

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
frosted 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
water freezes causing a
blockage. Drain water from
refrigerant or replace refrig-
erant.

If due to foreign particles,
remove 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 lubricant for contami-
nation.
AC362A
2 – ground : Battery voltage
RJIA2294E

TROUBLE DIAGNOSIS ATC-99
C
D E
F
G H
I
K L
M A
B
AT C
Revision: 2005 July 2005 FX
2. CHECK ECV CONTROL SIGNAL
1. Turn ignition switch OFF.
2. Reconnect compressor (ECV) connector.
3. Perform self-diagnosis. Refer to AT C - 5 3 , "
Self-diagnosis Func-
tion" .
4. Set in self-diagnosis STEP-4 (Code No. 45). Refer to AT C - 5 4 ,
"FUNCTION CONFIRMATION PROCEDURE" .
5. Confirm ECV control signal between unified meter and A/C amp. harness connector M57 terminal 45 (PU/W) and ground using
an oscilloscope.
OK or NG
OK >> Replace compressor.
NG >> GO TO 3.
3. CHECK CIRCUIT CONTINUITY BETWEEN ECV AND UNIFIED METER AND A/C AMP.
1. Turn ignition switch OFF.
2. Disconnect compressor (ECV) and unified meter and A/C amp. connector.
3. Check continuity between compressor (ECV) harness connector F6 terminal 3 (PU) and unified meter and A/C amp. harness
connector M57 terminal 45 (PU/W).
OK or NG
OK >> GO TO 4.
NG >> Repair harness or connector.
4. CHECK ECV
Check continuity between compressor (ECV) connector F6 terminals
2 and 3.
OK or NG
OK >> Replace unified meter and A/C amp.
NG >> Replace compressor.
RJIA2295E
RJIA1475E
3 – 45 : Continuity should exist.
RJIA2296E
2 – 3 : Continuity should exist.
RJIA2297E

ATC-104
TROUBLE DIAGNOSIS
Revision: 2005 July 2005 FX
Ambient Sensor CircuitAJS00154
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 E34 terminal 1 (Y) and ground.
OK or NG
OK >> GO TO 2.
NG >> GO TO 4.
RJIA2016E
RJIA1461E
1 – Ground : Approx. 5 V
RJIA2017E

TROUBLE DIAGNOSIS ATC-105
C
D E
F
G H
I
K L
M A
B
AT C
Revision: 2005 July 2005 FX
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 E34 terminal 2 (W) and unified meter and A/C amp. harness
connector M57 terminal 49 (W/G).
OK or NG
OK >> GO TO 3.
NG >> Repair harness or connector.
3. CHECK AMBIENT SENSOR
Refer to ATC-106, "
Ambient Sensor" .
OK or NG
OK >> 1. Replace unified meter and A/C amp. 2. Go to self-diagnosis AT C - 5 4 , "
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 - 5 4 , "
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 E34 terminal 1 (Y) and unified meter and A/C amp. harness con-
nector M57 terminal 39 (Y).
4. Check continuity between ambient sensor harness connector E34 terminal 1 (Y) and ground.
OK or NG
OK >> 1. Replace unified meter and A/C amp. 2. Go to self-diagnosis AT C - 5 4 , "
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

ATC-108
TROUBLE DIAGNOSIS
Revision: 2005 July 2005 FX
DIAGNOSIS PROCEDURE FOR IN-VEHICLE SENSOR
SYMPTOM: In-vehicle sensor circuit is open or shorted. (22 or −22 is
indicated on unified meter and A/C amp. as a result of performing
self-diagnosis STEP-2.)
1. CHECK VOLTAGE BETWEEN IN-VEHICLE SENSOR AND GROUND
1. Disconnect in-vehicle sensor connector.
2. Turn ignition switch ON.
3. Check voltage between in-vehicle sensor harness connector M46 terminal 1 (BR/W) and ground.
OK or NG
OK >> GO TO 2.
NG >> GO TO 4.
2. CHECK CIRCUIT CONTINUITY BETWEEN IN-VEHICLE 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 in-vehicle sensor harness connector M46 terminal 2 (W/G) and unified meter and A/C amp. harness
connector M57 terminal 49 (W/G).
OK or NG
OK >> GO TO 3.
NG >> Repair harness or connector.
3. CHECK IN-VEHICLE SENSOR
Refer to ATC-109, "
In-vehicle Sensor" .
OK or NG
OK >> 1. Replace unified meter and A/C amp. 2. Go to self-diagnosis AT C - 5 4 , "
FUNCTION CONFIRMATION PROCEDURE" and perform self-
diagnosis STEP-2. Confirm that code No. 20 is displayed.
NG >> 1. Replace in-vehicle sensor. 2. Go to self-diagnosis AT C - 5 4 , "
FUNCTION CONFIRMATION PROCEDURE" and perform self-
diagnosis STEP-2. Confirm that code No. 20 is displayed.
RJIA1452E
1 – Ground : Approx. 5 V
RJIA2022E
2 – 49 : Continuity should exist.
RJIA2023E