2005 INFINITI QX4 diagram

EC-500Revision: October 2005
DTC P1276, P1286 A/F SENSOR 1
2005 QX56
Wiring DiagramUBS00HAC
BANK 1
BBWA1700E

DTC P1276, P1286 A/F SENSOR 1
EC-505
C
D
E
F
G
H
I
J
K
L
MA
EC
Revision: October 20052005 QX56
4. CHECK A/F SENSOR 1 INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check harness continuity between A/F sensor 1 terminal and ECM terminal as follows.
Refer to Wiring Diagram.
4. Check harness continuity between the following terminals and ground.
Refer to Wiring Diagram.
5. Also check harness for short to power.
OK or NG
OK >> GO TO 5.
NG >> Repair open circuit or short to ground or short to power in harness or connectors.
5. CHECK INTERMITTENT INCIDENT
Perform EC-156, "
TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT" .
OK or NG
OK >> GO TO 6.
NG >> Repair or replace.
6. REPLACE AIR FUEL RATIO (A/F) SENSOR 1
Replace air fuel ratio (A/F) sensor 1.
CAUTION:

Discard any air fuel ratio (A/F) sensor which has been dropped from a height of more than 0.5 m
(19.7 in) onto a hard surface such as a concrete floor; use a new one.

Before installing new air fuel ratio (A/F) sensor, clean exhaust system threads (using Oxygen Sen-
sor Thread Cleaner tool J-43897-18 or J-43897-12) and approved anti-seize lubricant.
>>INSPECTION END
A/F sensor 1 terminal ECM terminal
Bank1116
275
535
656
Bank 2176
277
557
658
Continuity should exist.
Bank 1 Bank 2
A/F sensor 1 terminal ECM terminal A/F sensor 1 terminal ECM terminal
116176
275277
535557
656658
Continuity should not exist.

EC-510Revision: October 2005
DTC P1278, P1288 A/F SENSOR 1
2005 QX56
Wiring DiagramUBS00HAJ
BANK 1
BBWA1700E

DTC P1278, P1288 A/F SENSOR 1
EC-517
C
D
E
F
G
H
I
J
K
L
MA
EC
Revision: October 20052005 QX56
8. CHECK A/F SENSOR 1 INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check harness continuity between A/F sensor 1 terminal and ECM terminal as follows.
Refer to Wiring Diagram.
4. Check harness continuity between the following terminals and ground.
Refer to Wiring Diagram.
5. Also check harness for short to power.
OK or NG
OK >> GO TO 9.
NG >> Repair open circuit or short to ground or short to power in harness or connectors.
9. CHECK AIR FUEL RATIO (A/F) SENSOR 1 HEATER
Refer to EC-392, "
Component Inspection" .
OK or NG
OK >> GO TO 10.
NG >> GO TO 13.
10. CHECK MASS AIR FLOW SENSOR
Refer to EC-181, "
Component Inspection" .
OK or NG
OK >> GO TO 11.
NG >> Replace mass air flow sensor.
A/F sensor 1 terminal ECM terminal
Bank1116
275
535
656
Bank 2176
277
557
658
Continuity should exist.
Bank 1 Bank 2
A/F sensor 1 terminal ECM terminal A/F sensor 1 terminal ECM terminal
116176
275277
535557
656658
Continuity should not exist.

EC-522Revision: October 2005
DTC P1279, P1289 A/F SENSOR 1
2005 QX56
Wiring DiagramUBS00HAQ
BANK 1
BBWA1700E

DTC P1279, P1289 A/F SENSOR 1
EC-529
C
D
E
F
G
H
I
J
K
L
MA
EC
Revision: October 20052005 QX56
8. CHECK A/F SENSOR 1 INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check harness continuity between A/F sensor 1 terminal and ECM terminal as follows.
Refer to Wiring Diagram.
4. Check harness continuity between the following terminals and ground.
Refer to Wiring Diagram.
5. Also check harness for short to power.
OK or NG
OK >> GO TO 9.
NG >> Repair open circuit or short to ground or short to power in harness or connectors.
9. CHECK AIR FUEL RATIO (A/F) SENSOR 1 HEATER
Refer to EC-392, "
Component Inspection" .
OK or NG
OK >> GO TO 10.
NG >> GO TO 13.
10. CHECK MASS AIR FLOW SENSOR
Refer to EC-181, "
Component Inspection" .
OK or NG
OK >> GO TO 11.
NG >> Replace mass air flow sensor.
A/F sensor 1 terminal ECM terminal
Bank1116
275
535
656
Bank 2176
277
557
658
Continuity should exist.
Bank 1 Bank 2
A/F sensor 1 terminal ECM terminal A/F sensor 1 terminal ECM terminal
116176
275277
535557
656658
Continuity should not exist.

DTC P1444 EVAP CANISTER PURGE VOLUME CONTROL SOLENOID VALVE
EC-533
C
D
E
F
G
H
I
J
K
L
MA
EC
Revision: October 20052005 QX56
Wiring DiagramUBS00HAX
BBWA1687E

DTC P1444 EVAP CANISTER PURGE VOLUME CONTROL SOLENOID VALVE
EC-535
C
D
E
F
G
H
I
J
K
L
MA
EC
Revision: October 20052005 QX56
Diagnostic ProcedureUBS00HAY
1. CHECK EVAP CANISTER PURGE VOLUME CONTROL SOLENOID VALVE POWER SUPPLY CIR-
CUIT
1. Turn ignition switch OFF.
2. Disconnect EVAP canister purge volume control solenoid valve
harness connector.
3. Turn ignition switch ON.
4. Check voltage between EVAP canister purge volume control
solenoid valve terminal 1 and ground with CONSULT-II or tester.
OK or NG
OK >> GO TO 3.
NG >> GO TO 2.
2. DETECT MALFUNCTIONING PART
Check the following.

Harness connectors E2, F32

IPDM E/R harness connector E119

Harness for open or short between EVAP canister purge volume control solenoid valve and IPDM E/R

Harness for open or short between EVAP canister purge volume control solenoid valve and ECM
>> Repair harness or connectors.
3. CHECK EVAP CANISTER PURGE VOLUME CONTROL SOLENOID VALVE OUTPUT SIGNAL CIR-
CUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check harness continuity between ECM terminal 45 and EVAP canister purge volume control solenoid
valve terminal 2. Refer to Wiring Diagram.
4. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 4.
NG >> Repair open circuit or short to ground or short to power in harness or connectors.
BBIA0366E
Voltage: Battery voltage
PBIB2245E
Continuity should exist.