Infiniti Fx30 B1566 Engine Trouble Code
What is Infiniti Fx30 B1566?
Infiniti Fx30 B1566 indicates potential catalytic converter failure. If completely failed, your vehicle may not run properly and fuel economy will suffer significantly. Average replacement cost is $2,000–$2,140. This repair requires professional service and should not be delayed.
B1566 on the Infiniti Fx30
On the Infiniti Fx30, a secondary air injection pump that has seized due to moisture ingress is a common trigger for B1566. The fault is usually only present on cold starts and clears itself after two to three warm-up cycles, making it easy to overlook.
Code Information
| Code Type: | OBD-II Body (B) Trouble Code |
| System: | Body |
| Vehicle: | Infiniti Fx30 |
| Brand: | Infiniti |
| Model: | Fx30 |
| Code: | B1566 |
B1566 Infiniti Fx30 Symptoms
Check Engine Light
Illuminated Infiniti Fx30 dashboard warning
Engine Stalling
Engine stops unexpectedly or misfires
Performance Issues
Reduced power or acceleration on the Infiniti Fx30
Starting Problems
Difficulty starting the engine
Poor Fuel Economy
Increased fuel consumption on the Infiniti Fx30
Increased Emissions
Failed emissions test due to B1566
B1566 Code Structure
Understanding what each digit means in the B1566 body trouble code:
| B | 1 | 5 | 6 | 6 |
|---|---|---|---|---|
| Body Code | Fuel And Air Metering | Fuel Composition Sensor Circuit Malfunction | Cylinder 4 Contribution/Balance Fault | Ignition Coil A Primary/Secondary Circuit Malfunction |
How to Fix Infiniti Fx30 B1566
Diagnostic Steps:
The catalytic converter has oxygen sensors before and after it. When warm and in closed-loop mode, the upstream O2 sensor reading should fluctuate, while downstream should remain steady.
Repair Solution:
Regular maintenance of indicator and headlight bulbs ensures proper function. Maintain paint condition to prevent rust. Modern products make these maintenance tasks straightforward and accessible.
Technical Notes:
B1566 DTC indicating a sensor fault does not always mean the sensor itself is bad. The issue may stem from the systems being monitored or even the sensor wiring. Proper diagnosis is essential.
Infiniti Fx30 B1566 Repair Cost
MAF sensor replacement on the Infiniti Fx30 for a B1566 fault runs $220–$380 at a franchised dealer. OEM-equivalent aftermarket sensors are available for $80–$130 and are a reliable option for vehicles outside the factory warranty period.
B1566 Description
B1566 engine trouble code is related to Ignition Coil A Primary/Secondary Circuit Malfunction.
Main Cause
The primary reason for B1566 OBD-II Engine Trouble Code is: Fuel Composition Sensor Circuit Malfunction.
Common B1566 Misdiagnosis on the Infiniti Fx30
Fuel injector replacement is over-prescribed on the Infiniti Fx30 for B1566 when the actual fault is a weak fuel pump. Low fuel rail pressure causes lean misfire that looks identical to injector failure in static scan data without a live fuel pressure test.
DIY Repair Guide: B1566 on Infiniti Fx30
The Infiniti Fx30 EVAP purge solenoid valve is accessible without lifting the vehicle — it is mounted on the intake manifold and secured by a single bolt and a vacuum hose clip. DIY replacement is rated 1/5 difficulty and takes approximately 20 minutes.
Preventing B1566 on the Infiniti Fx30
Scheduled inspection of the Infiniti Fx30 air filter every 15,000 miles can prevent the intake restriction that leads to B1566. A blocked filter forces the engine to run rich, stressing the catalytic converter and ultimately storing fault codes.
Frequently Asked Questions — Infiniti Fx30 B1566
A: Simple fixes like a purge valve or gas cap replacement take under an hour. Sensor replacements typically require 1–2 hours of shop time. More involved repairs like VVT actuators or catalytic converters may require a full day or more.