B1646 Ford Explorer Iii Diagnostic Trouble Code

B1646 Ford Explorer Iii code definition:
B1646 is a kind of OBD-II Diagnostic B-Body Diagnostic Trouble Code for Ford Explorer Iii.

B1646 Ford Explorer Iii is described as Oxygen Sensor Circuit No Activity Detected (Bank 1, Sensor 1). This means there's a problem in the front oxygen sensor on Bank 1, as the O2 sensor is inactive. 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 B1646 Ford Explorer Iii diagnostic trouble code may include:

Misfire
Misfire
The light may stay on or light intermittently as the DPF regenerates. The engine will be sluggish on acceleration.
Reduction in engine performance, especially at low RPM levels

Possible Causes :

Low fuel pressure caused by a clogged filter, failing fuel pump, failed fuel pressure regulator or clogged or leaking injectors.
Low fuel pressure caused by a clogged filter, failing fuel pump, failed fuel pressure regulator or clogged or leaking injectors.
An air leak forward of the DPF will change the sensor readings resulting in the code

Common Misdiagnoses

TP Sensor Learn Not Complete Problem
Low Coolant Circuit Problem
Cruise Control System - Vehicle Accel Too High Problem
TFP Valve Position Switch-Drive Without Drive Ratio Problem
Problem

Repair Processes :

Look for damage to the tank indicating impact that may have damaged the fuel pump or sender. Use the DVOM to test resistance and continuity on all system circuits if actuator and sensor resistance levels are in compliance with manufacturer's specifications.

Process Tips

Diagnostic trouble code B1646 Ford Explorer Iii 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 B1646 Ford Explorer Iii.

Fortunately, B1646 Ford Explorer Iii is a fairly common OBD code, meaning that it applies to all makes and models of vehicles made after 1996.