2005 INFINITI QX4 Factory Service Manual

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INFINITI QX4 2005  Factory Service Manual EC-298Revision: October 2005
DTC P0420, P0430 THREE WAY CATALYST FUNCTION
2005 QX56
DTC P0420, P0430 THREE WAY CATALYST FUNCTIONPFP:20905
On Board Diagnosis LogicUBS00H4F
The ECM monitors the switchin

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INFINITI QX4 2005  Factory Service Manual DTC P0420, P0430 THREE WAY CATALYST FUNCTION
EC-299
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8. Select “DTC & SRT CONFIRMATION” then “SRT WORK SUP-
PORT” mode with CONSULT-II.

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INFINITI QX4 2005  Factory Service Manual EC-300Revision: October 2005
DTC P0420, P0430 THREE WAY CATALYST FUNCTION
2005 QX56
Diagnostic ProcedureUBS00H4I
1. CHECK EXHAUST SYSTEM
Visually check exhaust tubes and muffler for dent.
OK or NG
OK

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INFINITI QX4 2005  Factory Service Manual DTC P0420, P0430 THREE WAY CATALYST FUNCTION
EC-301
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5. CHECK INJECTORS
1. Stop engine and then turn ignition switch ON.
2. Check voltage betwe

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INFINITI QX4 2005  Factory Service Manual EC-302Revision: October 2005
DTC P0420, P0430 THREE WAY CATALYST FUNCTION
2005 QX56
7. CHECK FUNCTION OF IGNITION COIL-II
1. Turn ignition switch OFF.
2. Disconnect spark plug and connect a known-good

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INFINITI QX4 2005  Factory Service Manual DTC P0420, P0430 THREE WAY CATALYST FUNCTION
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11 .  CHECK INTERMITTENT INCIDENT
Refer to EC-156, "
TROUBLE DIAGNOSIS FOR INTERMITTENT IN

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INFINITI QX4 2005  Factory Service Manual EC-304Revision: October 2005
DTC P0441 EVAP CONTROL SYSTEM
2005 QX56
DTC P0441 EVAP CONTROL SYSTEMPFP:14950
System DescriptionUBS00H4J
NOTE:
If DTC P0441 is displayed with other DTC such as P2122, P21

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INFINITI QX4 2005  Factory Service Manual DTC P0441 EVAP CONTROL SYSTEM
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 WITH CONSULT-II
1. Start engine and warm it up to normal operating temperature.
2. Turn ignition switch