2006 INFINITI QX56 diagram

DTC P0137, P0157 HO2S2EC-261
C
DE
F
G H
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K L
M A
EC
Revision: November 2009 2006 QX56
3. CHECK HO2S2 GROUND CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Disconnect heated oxygen sensor 2 harness connector.
3. Disconnect ECM harness connector.
4. Check harness continuity between ECM terminal 78 and HO2S2 terminal 4. Refer to Wiring Diagram.
5. 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.
4. CHECK HO2S2 INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Check harness continuity between ECM terminal and HO2S2 terminal as follows. Refer to Wiring Diagram.
2. Check harness continuity between the following terminals and ground. Refer to Wiring Diagram.
3. 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. Continuity should exist.
BBIA0435E
DTC
Te r m i n a l s
Bank
ECM Sensor
P0137 5511
P0157 7412
Continuity should exist.
DTC Te r m i n a l s
Bank
ECM Sensor
P0137 5511
P0157 7412
Continuity should not exist.

DTC P0138, P0158 HO2S2EC-267
C
DE
F
G H
I
J
K L
M A
EC
Revision: November 2009 2006 QX56
Wiring DiagramUBS00N73
BANK 1
BBWA1678E

DTC P0138, P0158 HO2S2EC-271
C
DE
F
G H
I
J
K L
M A
EC
Revision: November 2009 2006 QX56
2. CHECK HO2S2 GROUND CIRCUIT FOR OPEN AND SHORT
1. Disconnect heated oxygen sensor 2 harness connector.
2. Disconnect ECM harness connector.
3. Check harness continuity between ECM terminal 78 and HO2S2 terminal 4. Refer to Wiring Diagram.
4. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 3.
NG >> Repair open circuit or short to ground or short to power in harness or connectors.
3. CHECK HO2S2 INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Check harness continuity between ECM terminal and HO2S2 terminal as follows. Refer to Wiring Diagram.
2. Check harness continuity between the following terminals and ground. Refer to Wiring Diagram.
3. Also check harness for 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. Continuity should exist.
BBIA0435E
DTC
Te r m i n a l s
Bank
ECM Sensor
P0138 5511
P0158 7412
Continuity should exist.
DTC Te r m i n a l s
Bank
ECM Sensor
P0138 5511
P0158 7412
Continuity should not exist.

EC-274Revision: November 2009
DTC P0138, P0158 HO2S2
2006 QX56
3. CHECK HO2S2 GROUND CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Disconnect heated oxygen sensor 2 harness connector.
3. Disconnect ECM harness connector.
4. Check harness continuity between ECM terminal 78 and HO2S2 terminal 4. Refer to Wiring Diagram.
5. 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.
4. CHECK HO2S2 INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Check harness continuity between ECM terminal and HO2S2 terminal as follows. Refer to Wiring Diagram.
2. Check harness continuity between the following terminals and ground. Refer to Wiring Diagram.
3. 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. Continuity should exist.
BBIA0435E
DTC
Terminals
Bank
ECM Sensor
P0138 5511
P0158 7412
Continuity should exist.
DTC Terminals
Bank
ECM Sensor
P0138 5511
P0158 7412
Continuity should not exist.

EC-280Revision: November 2009
DTC P0139, P0159 HO2S2
2006 QX56
Wiring DiagramUBS00H2S
BANK 1
BBWA1678E

DTC P0139, P0159 HO2S2EC-285
C
DE
F
G H
I
J
K L
M A
EC
Revision: November 2009 2006 QX56
3. CHECK HO2S2 GROUND CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Disconnect heated oxygen sensor 2 harness connector.
3. Disconnect ECM harness connector.
4. Check harness continuity between ECM terminal 78 and HO2S2 terminal 4. Refer to Wiring Diagram.
5. 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.
4. CHECK HO2S2 INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Check harness continuity between ECM terminal and HO2S2 terminal as follows. Refer to Wiring Diagram.
2. Check harness continuity between the following terminals and ground. Refer to Wiring Diagram.
3. 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. Continuity should exist.
BBIA0435E
DTC
Te r m i n a l s
Bank
ECM Sensor
P0139 5511
P0159 7412
Continuity should exist.
DTC Te r m i n a l s
Bank
ECM Sensor
P0139 5511
P0159 7412
Continuity should not exist.

EC-290Revision: November 2009
DTC P0171, P0174 FUEL INJECTION SYSTEM FUNCTION
2006 QX56
Wiring DiagramUBS00L0N
BANK 1
BBWA2090E

DTC P0171, P0174 FUEL INJECTION SYSTEM FUNCTIONEC-295
C
DE
F
G H
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J
K L
M A
EC
Revision: November 2009 2006 QX56
3. CHECK A/F SENSOR 1 INPUT SIGNAL CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect corresponding A/F sensor 1 harness connector.
3. Disconnect ECM harness connector.
4. Check harness continuity between the following terminals. Refer to Wiring Diagram.
5. Check harness continuity between the following terminals and ground. Refer to Wiring Diagram.
6. Also check harness for 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.
A/F sensor 1 terminal ECM terminal
Bank 1 11
6
27 5
53 5
65 6
Bank 2 17
6
27 7
55 7
65 8
Continuity should exist.
Bank 1 Bank 2
A/F sensor 1 terminal ECM terminal A/F sensor 1 terminal ECM terminal 11 617 6
27 527 7
53 555 7
65 665 8
Continuity should not exist.
BBIA0376E