2011 INFINITI QX56 Factory Service Manual

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INFINITI QX56 2011  Factory Service Manual 
P0138, P0158 HO2S2EC-249
< DTC/CIRCUIT DIAGNOSIS > [VK56VD]
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P0138, P0158 HO2S2
DTC LogicINFOID:0000000006217817
DTC DETECTION LOGIC
The heated oxygen sensor 2 has a mu

Page 2274 of 5598

INFINITI QX56 2011  Factory Service Manual 
EC-250
< DTC/CIRCUIT DIAGNOSIS >[VK56VD]
P0138, P0158 HO2S2
1.PRECONDITIONING
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wai

Page 2275 of 5598

INFINITI QX56 2011  Factory Service Manual 
P0138, P0158 HO2S2EC-251
< DTC/CIRCUIT DIAGNOSIS > [VK56VD]
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YES >> INSPECTION END
NO >> Go to 
EC-251, "
Diagnosis Procedure".
Component Function CheckINFOID:000000000

Page 2276 of 5598

INFINITI QX56 2011  Factory Service Manual 
EC-252
< DTC/CIRCUIT DIAGNOSIS >[VK56VD]
P0138, P0158 HO2S2
Which malfunction is detected?
A>>GO TO 2
B>>GO TO 8.
2.CHECK HEATED OXYGEN SENSOR 2 CONNECTOR
1. Disconnect heated oxygen sensor 2 (HO2S2)

Page 2277 of 5598

INFINITI QX56 2011  Factory Service Manual 
P0138, P0158 HO2S2EC-253
< DTC/CIRCUIT DIAGNOSIS > [VK56VD]
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 Discard any heated oxygen sensor which has been dr
opped from a height of more than 0.5 m (19.7
in) onto

Page 2278 of 5598

INFINITI QX56 2011  Factory Service Manual 
EC-254
< DTC/CIRCUIT DIAGNOSIS >[VK56VD]
P0138, P0158 HO2S2
11 .CHECK HEATED OXYGEN SENSOR 2
Refer to  EC-254, "
Component Inspection (HO2 sensor 2)".
Is the inspection result normal?
YES >> GO TO 13

Page 2279 of 5598

INFINITI QX56 2011  Factory Service Manual 
P0138, P0158 HO2S2EC-255
< DTC/CIRCUIT DIAGNOSIS > [VK56VD]
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2. Turn ignition switch OFF and wait at least 10 seconds.
3. Start engine and keep the engine speed between

Page 2280 of 5598

INFINITI QX56 2011  Factory Service Manual 
EC-256
< DTC/CIRCUIT DIAGNOSIS >[VK56VD]
P0138, P0158 HO2S2
 Before installing new oxygen sensor, clean exh
aust system threads using Oxygen Sensor Thread
Cleaner [commercial service tool (J-43897-1