B2391 Nissan Sunny Diagnostic Trouble Code

B2391 Nissan Sunny code definition:
B2391 is a kind of OBD-II Diagnostic B-Body Diagnostic Trouble Code for Nissan Sunny.

B2391 Nissan Sunny is described as Oxygen Sensor Circuit No Activity Detected Bank 2 Sensor 1. This code appears when the PCM (powertrain control module, also known as ECM or engine control module in other brands) remains at or close the 0.450 set voltage point. If the car doesn't start, they will proceed by testing the voltage at the fuel pump connector and see if the fuel pump relay, fuse, and PCM circuitry should be inspected.

Symptoms

Symptoms of a B2391 Nissan Sunny diagnostic trouble code may include:

Cherry red hot catalytic converter
Poor acceleration
The light may stay on or light intermittently as the DPF regenerates. The engine will be sluggish on acceleration.
Rich or lean exhaust

Possible Causes :

Faulty IMRC actuator relay (if equipped)
A large air leak at or near the number one oxygen sensor would also cause a lean mixture.
An air leak forward of the DPF will change the sensor readings resulting in the code

Common Misdiagnoses

Vehicle Speed Output Circuit Problem
Cruise Control Servo Indicates Low Problem
A/C System High Pressure High Temperature Problem
PCM Stack Overrun Problem
Transmission Control Module Reprogrammable Memory Problem

Repair Processes :

Check to make sure they are not burnt or corroded. If in doubt, get some Electrical Contact cleaner at any parts store if cleaning of the terminals is needed. With the valve disconnected, the red voltmeter lead should be attached to the IMRC valve power wire and the black voltmeter lead connected to ground.

Process Tips

Diagnostic trouble code B2391 Nissan Sunny is not difficult to diagnose and repair. Thus, it always pays to have a qualified technician to look after your vehicle should this error code arise.

Diagnosing this code requires the engine to be in good running shape, without unmetered air entering the engine. If other codes that relates to misfiring condition, lean running or air entering the engine is present, then you must first fix those error codes before B2391 Nissan Sunny.

Fortunately, B2391 Nissan Sunny is a fairly common OBD code, meaning that it applies to all makes and models of vehicles made after 1996.