This code indicates that the engine computer has detected that the 'B' (typically exhaust) camshaft on Bank 2 is more delayed in its timing than the target commanded by the system. It usually points to a malfunction in the variable valve timing (VVT) system, most commonly related to oil flow problems or a stuck actuator.
The oil control solenoid for Bank 2 can become stuck open or clogged with sludge, continuously allowing oil pressure to retard the camshaft timing.
The mechanical actuator on the camshaft can bind or fail internally, preventing it from returning to the default timing position.
VVT systems rely on proper oil pressure and clean oil; low oil level or contaminated oil can prevent the system from operating correctly.
An open circuit, short to power/ground, or corroded connector in the OCV circuit can keep the solenoid in a retarded state.
A faulty engine computer is a very rare cause, only occurring if the internal driver for the OCV has failed.
The definition is universal; the diagnostics are engine-specific. Open your vehicle for the codes documented for it:
Almost never. Many drivers are mistakenly told to replace the PCM for this code, but it is almost always caused by oil flow issues, a stuck VVT solenoid, or a failed camshaft actuator. Replacing the PCM should be the absolute last resort.
It is not recommended. Driving with retarded camshaft timing can cause poor engine performance, stalling, and potentially severe engine damage if the timing is drastically out of specification.
Bank 2 refers to the side of the engine that does not contain cylinder #1. On V6 or V8 engines, you must identify which side is Bank 2 to inspect and test the correct solenoid and actuator.
In most manufacturer conventions, 'A Camshaft' refers to the intake camshaft and 'B Camshaft' refers to the exhaust camshaft, though it is best to confirm with the specific vehicle's service manual.