2019 Infiniti M35 V6-3.5L (VQ35HR) Diagnostic and Repair Information Page 347
Check the voltage between ECM harness connector terminals under the following condition.
Is the inspection result normal?
YES - INSPECTION END
NO - GO TO 5.
5.CHECK HEATED OXYGEN SENSOR 2-III
Check the voltage between ECM harness connector terminals under the following condition.
Is the inspection result normal?
YES - INSPECTION END
NO - GO TO 6.
6.REPLACE HEATED OXYGEN SENSOR 2
Replace malfunctioning heated oxygen sensor 2.
CAUTION:
- Discard any heated oxygen 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 oxygen sensor, clean exhaust system threads using Oxygen Sensor Thread
Cleaner [commercial service tool (J-43897-18 or J-43897-12)] and approved anti-seize lubricant
(commercial service tool).
- INSPECTION END
P0171
P0171, P0174 FUEL INJECTION SYSTEM FUNCTION
DTC Logic
DTC DETECTION LOGIC
With the Air/Fuel Mixture Ratio Self-Learning Control, the actual mixture ratio can be brought closely to the theoretical mixture ratio based on
the mixture ratio feedback signal from air fuel ratio (A/F) sensor 1. The ECM calculates the necessary compensation to correct the offset between
the actual and the theoretical ratios.
In case the amount of the compensation value is extremely large (the actual mixture ratio is too lean), the
ECM judges the condition as the fuel injection system malfunction and illuminates the MIL (2 trip detection logic).
