B1245 Nissan Frontier Diagnostic Trouble Code

B1245 Nissan Frontier code definition:
B1245 is a kind of OBD-II Diagnostic B-Body Diagnostic Trouble Code for Nissan Frontier.

B1245 Nissan Frontier is defined as Knock Sensor Circuit Range Performance (Bank 1 or Single Sensor). This refers to camshaft timing, which in this case is over-retarded. The PCM then uses this data to provide the right strategies for the fuel delivery and ignition timing of the engine.

Symptoms

Symptoms of a B1245 Nissan Frontier diagnostic trouble code may include:

Hesitation upon acceleration
Excessive exhaust leak
Rich or lean exhaust
If the DPF is not cleared the ECU will revert to the "Limp Home Mode" until the situation is corrected

Possible Causes :

A large air leak at or near the number one oxygen sensor would also cause a lean mixture.
Faulty IMRC actuator relay (if equipped)
Some aftermarket accessories and performance modifications

Common Misdiagnoses

Crankshaft Position Sensor Circuit Performance Problem
TP Sensor Learn Not Complete Problem
Low Coolant Circuit Problem
Cruise Control System - Vehicle Accel Too High Problem
Kick-Down Switch Failed Short Problem

Repair Processes :

If the scan tool has that capability, and the scan tool can operate the IMRC valves, then the problem is either resolved and a simple code clearing is all that's left or a new PCM would be called for. 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 B1245 Nissan Frontier 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 B1245 Nissan Frontier.

Fortunately, B1245 Nissan Frontier is a fairly common OBD code, meaning that it applies to all makes and models of vehicles made after 1996.